Ours herbs (elsewhere also shrubs, trees, and vines). Stems often 4-angled. Leaves opposite, simple, often with 3 to 9 prominent, nearly parallel veins; ours estipulate. Flowers cymose, perfect, regular, mostly 4- or 5-merous, perigynous, hypanthium variously shaped. Sepals valvate on the rim of the hypanthium. Petals convolute in bud. Stamens usually in 2 whorls, often dimorphic, in ours usually twice as many as the petals, filaments commonly twisted to one side of the flower at anthesis, anthers variously dehiscent, sometimes appendaged. Ovary with (2)3 to 5(15) carpels and as many locules, rarely unilocular. Fruit a many-seeded capsule (as in ours) or berry. Seeds usually small, without endosperm, cotyledons unequal.

About 215 genera and 4,750 species of tropical and subtropical regions, especially S. America; 1 genus with 5 species in TX; 2 species in our area.

Some taxa have food, timber, dye, or ornamental uses (Mabberley 1987).

Perennial herbs, some suffrutescent, from rather woody caudices, rhizomes, rhizomes, tubers, or some combination thereof. Stems 1 to several, simple or branched, sometimes spongy-thickened below or with a shredding epidermis, round below, more or less 4-angled above, edges winged or unwinged and faces concave to convex, often the opposite pairs different, glabrous to glandular pubescent and/or hirsute. Leaves opposite, decussate, sessile or short-petiolate, commonly with 3 major palmate, parallel veins, blades suborbicular to linear-lanceolate, margins ciliate to serrate. Flowers in cymes (rarely solitary and not in ours), showy, few to many, sessile or with pedicels shorter than the hypanthium, subtended by bracts similar to the leaves but smaller and often deciduous. Hypanthium essentially urceolate below, constricted above and then more or less expanding above the neck, composed of 2 layers, fused to the ovary so the gynoecium mostly inferior, but at anthesis the 2 layers separating and the capsule appearing superior. Calyx lobes 4, on the outer layer of the hypanthium, erect to recurved. Petals 4, borne on the inner layer of the hypanthium, free, asymmetrical with the right side larger than the left, short-clawed, commonly tipped with a bristly extension of the midvein, ascending to spreading, fugacious, rose to purple or in some white or yellow. Stamens 8, in 2 whorls on the inner hypanthium layer, subequal, filaments slender, downcurving, usually all pulled to the bottom of the flower, each with a small appendage at the juncture with the anther; anthers basifixed, with terminal pores, straight to curved or sigmoid. Ovary fully enclosed in the hypanthium, 4-celled, placentation axile; style 1, linear, stigma truncate. Fruit a loculicidal capsule. Seeds many, in most TX material curved like a snail shell, surface adornment various.

11 species of N. Amer., chiefly in the SE. U.S. but one species extending to Canada and another to Mex.; 5 in TX; 2 here.

Some, but not usually ours, are cultivated for ornament (Mabberley 1987).

NOTE: Interspecific hybrids between some taxa, including ours, are common. In addition, vital stem characters are easily lost in pressing, so identifications should be made from fresh material if possible. A useful referemce is Kral and Bostick (1969).

1. Faces of midstem markedly unequal, one pair flat to concave, narrower and paler than the other pair, which are broader , convex to rounded, and darker green; neck of

hypanthium about as long as the body of the hypanthium; petals usually glabrous ...............

Our most common Rhexia locally. Several other varieties are recognized. One other, var. interior (Penn.) Kral & Bostick, reaches TX (Kral and Bostick 1969) but is not present in our area as far as is now known. It is actually similar to R. virginica, below, in stem-face characters, but lacks the winged angles and has a hypanthium neck longer than the body [R. interior Penn.].

Shrubs or trees (rarely herbs). Leaves alternate or opposite, simple, entire or essentially so, estipulate, usually deciduous. Flowers small, regular, perfect or unisexual, 4- or 5-merous, often in cymose arrangements, sometimes subtended by showy bracts. Calyx small or rudimentary. Petals 0 or 4 or 5. Stamens 4 to 12, sometimes in 2 series, filaments elongate; anthers introrse. Ovary inferior, of (1)2 to 4(5) carpels, styles 1 or 2, locules 1 or 2. Fruit drupe-like, with 1 to 5 locules and usually 1 pyrene per locule.

As treated here the family includes the Nyssaceae and comprises 3 genera and 7 species in TX; 2 genera and 3 species here. The trend in recent years has been to separate the Nyssaceae from the Cornaceae on the basis of various factors, including the 5-merous perianth of the Nyssaceae. However, the two groups are undoubtedly closely related and are retained as a unit by some systematists such as Thorne (See Zomlefer 1994). It is perhaps easiest for the student to interpret them as one family. If the families are separated, our Nyssa move to the Nyssaceae (3 genera and 8 species) and Cornus remains in the Cornaceae (12 genera and 90 species). The other TX genus, Garrya, can be put into its own family, the Garryaceae (1 genus, 13 species.)

Some taxa are cultivated ornamentals, some are timber sources, and some have edible fruit (Mabberley, 1987).

Ours shrubs or small trees (other taxa sometimes perennial herbs). Leaves opposite, petiolate, estipulate, entire, lateral veins curved upwards, nearly parallel. Inflorescence an open cyme or a head-like cluster subtended by 4 showy bracts. Flowers small, regular, perfect. Calyx of 4 minute teeth. Petals and stamens 4, inserted on the margin of an epigynous disk; ovary inferior, bicarpellate and with (1)2 locules, style 1, stigma flattened or capitate. Fruit drupe-like, with a (1-)2-seeded stone.

About 45 species of the N. temperate region, rare in S. Amer. and Afr.; 3 in TX; 2 here.

C. florida is the most common cultivated dogwood, prized for its showy flowers, but other species are cultivated for flowers and colorful fruit, including C. kousa and C. mas. Others have brightly colored winter twigs. The wood of some species has been used for tools, cabinet work, and other small objects. The fruits of some are edible (Mabberley 1987) or provide food for wildlife, including game birds, while deer browse the twigs and leaves (Elias 1980).

A field test for dogwood identification involves tearing a leaf gently in half across its width. The two halves of a dogwood leaf usually remain attached by cobwebby threads of vascular tissue.

This plant is one of our most striking native flowering trees. It is commonly planted and some strains have been developed with decidedly pink bracts or variegated leaves. Plants along the E. seaboard of the U.S. have fallen prey to an anthracnose disease not yet a serious problem in TX. Songbirds and squirrels eat the fruits, though they are supposedly poisonous to humans. The wood is close-grained and hard, useful for tool handles and other small objects (Elias 1980).

Whitetail deer browse the foliage; songbirds, gamebirds, and small mammals eat the fruits (Elias 1980).

Trees or shrubs with alternate, simple, deciduous, entire or rarely slightly-toothed leaves commonly crowded at the ends of the branchlets. Flowers perfect or unisexual. Staminate flowers many in crowded clusters, calyx small, 5-parted; petals small and fleshy, soon falling or else entirely absent; stamens 5 to 12, inserted on the outer rim of the staminal disk. Pistillate flowers single or in small, sessile, bracted clusters of up to 8; style 1, elongate, ovary 1-celled. Fruit a 1-seeded drupe.

5 species of N. Amer., China, and Indomalaysia; 2 in TX; 1 here. Placed by some in the family Nyssaceae.

Some species are used for timber or are cultivated for ornamental fall color (Mabberley 1987).

1. N. sylvatica Marsh Medium to large tree to 30(40) m tall, branches spreading horizontally or drooping; bark light brown, with age deeply furrowed and with scaly vertical ridges; young branchlets reddish-brown, sparsely pubescent, becoming glabrous. Leaves alternate, often crowded at the tips of the branchlets, petioles to 2 cm long; blades to 14 cm long and 7 cm broad, obovate to broadly elliptic or linear to oblanceolate, ca. 2 to 3 times longer than wide, apically rounded to abruptly acuminate or acute, rounded to tapered basally, margins entire or sometimes wavy, rarely with any teeth, glabrous (or nearly so) and lustrous above, glabrate to glabrous below. Staminate flowers pedicellate, in an umbellate or compact raceme. Pistillate flowers 2 or more in pubescent, peduncled clusters. Fruits usually in 2's or 3's, ellipsoid, dark blue, 1 to 1.5 m long, flesh bitter to acid; stone hard, sometimes ribbed. Moist uplands or more usually in bottomland woods and in and around bogs. E. TX; ME to FL, W. to MI, IL, SE. MO, E. OK, and TX. Mar.-May. Fall color red to maroon.

Two varieties have been described for TX, both probably present. Our plants however, seem to be nearly all of the first variety. Kartesz (1998) recognizes the second as a distinct species .

var. sylvatica Black Gum, Sour-gum, Pepperidge. Leaves obovate to broadly elliptic, ca. twice as long as wide, to 14 cm long, abruptly acuminate to rounded apically, usually thin-textured; young petioles densely long-pilose; fruiting peduncles usually longer than 3 cm; flesh of fruit more or less acid. Typically in upland woods and stream bottoms, on light-textured soils. ME to NY and S. Ont., S. to FL and TX; disjunctly in Mex. Apr-May. [Includes var. dilatata Fern. and var. caroliniana (Poir.) Fern.].

var. biflora (Walt.) Sarg. Black Gum, Swamp Tupelo. Trunk base swollen when in standing water; leaves mostly linear to oblanceolate, usually 3 times longer than broad, usually leathery, rounded to acute apically, to 12 cm long, rarely to 4 cm broad; fruiting peduncles usually less than 3 cm long; fruit bitter. In seasonally flooded swamps, in low wet woods, and on stream banks. E. TX; DE and MD, S. to FL and TX. Mar.-Apr. [N. biflora Walt.].

Herbaceous or shrubby aerial parasites. Stems evergreen, usually branched, brittle, the nodes usually swollen and articulated. Leaves opposite, simple, entire, evergreen or some (not ours) reduced to scales. Herbage pubescent or glabrous. Plants monoecious or dioecious, flowers small, less than 2 mm long, clustered at the nodes or in spikes or cymes. Calyx segments 2 to 4, valvate, Corolla none. Staminate flowers with stamens as many as the sepals and opposite them, fused to them or free. Pistillate flowers with ovary inferior, of 3 to 4 united carpels, unilocular, style 1, stigma terminal. Ovules none, the 2 embryo sacs originating from short placental columns. Fruit a berry with 1(2) testa-less seeds, viscid tissue, and persistent sepals.

8 genera and 450 species more or less worldwide, mostly in the tropics and subtropics; 2 genera and 10 species in TX; 1 species here.

The plants can be serious parasites, especially in plantation trees. Viscum (Old World) and Phoradendron (New World) are the genera commonly used as Christmas decorations (Mabberley 1987).

Parasitic shrubs, leaves and sometimes stems green and photosynthetic. Leaves evergreen, opposite, well-developed (as in ours) or in some reduced to scales. Plants dioecious, flowers ca. 2 mm long, in cylindrical, spike-like, axillary inflorescences with the flowers sunken into the rachis, 1 at the apex an the others 3-ranked. Staminate inflorescence usually with 5 to 60 flowers. Pistillate inflorescence with 4 to 11 flowers. Calyx segments usually (2)3(4), free, deltoid, scale-like, persistent, seldom erect and never spreading, commonly incurved. Staminate flower with 1 sessile 2-celled anther at the base of each sepal. Pistillate flower with an inferior ovary below the persistent sepals, unilocular. Fruit small, drupe-like, mesocarp mucilaginous, usually whitish.

190 species in America, especially in the tropics; 7 in TX; 1 here. This treatment follows Wiens (1964). The author of this article communicated to the editors of The Flora of the Great Plains that he felt this to be a better treatment of the P. tomentosum-P. serotinum complex than the treatment presented by Correll and Johnston (1970); see GPFA (1986).

P. serotinum is the species most commonly sold as a floral decoration (Mabberley, 1987). The leaves and stems are toxic and the berries may be poisonous if eaten in large quantities. It is the berries that are responsible for the few reported fatal cases. Symptoms of poisoning are usually those of severe gastroenteritis (Lampe 1985).

1. P. tomentosum (DC.) Engelm. ex Gray Mistletoe, Injerto. Shrubs to 1 m or more in diameter, yellow-green, moderately to densely stellate-pubescent on younger parts, older parts more lightly so. Leaf blades elliptic-obovate to orbicular, 16 to 28(40) mm long, 9 to 22 mm broad, moderately to densely pubescent, obtuse to rounded apically, basally rounded to attenuate, leathery, veins prominent to obscure; petiole 2 to 4 mm long or obsolete, commonly more densely pubescent than the blade. Staminate inflorescence with 2 to 6 segments, each with 15 to 42 flowers. Pistillate inflorescence with 2 to 6 segments, each with 6 to 11 flowers. Fruit whitish, 4 to 6 mm in diameter, glabrous or nearly so. Flowering Dec.-Mar. Parasitic primarily on Prosopis (Mesquite) or other legumes, Celtis, Ulmus, and sometimes Quercus. S., Cen., and W. TX. [Includes var. tomentosum, as the former var. macrophyllum (Engelm.) Wiens is now accorded separate specific status (e.g. see Hatch, et al. 1990); P. flavescens of authors and var. tomentosum (DC.) Engelm. in Brewer and Watson; P. serotinum (Raf.) M. C. Johnst. var. pubescens (Engelm.) M. C. Johnst.].

Tull (1987) reported that pale tan, yellow, and green dyes can be made from this plant.

Texas material woody vines, shrubs, or small trees. Leaves simple, alternate or opposite, petiolate; stipules absent or minute and deciduous. Inflorescences axillary cymes or terminal racemes or panicles. Flowers perfect or rarely unisexual, 4- or 5-merous, regular; pedicels jointed. Sepals in ours united basally. Petals free, usually imbricate. Stamens 4 to 10, inserted on the margin of a disk that occupies nearly the whole of the bottom of the calyx and sometimes obscures the ovary. Ovary on or partly surrounded by the disk, of 1 to 5 united carpels with as many locules, free of the calyx; style 1, ovules (1)2 to 10. Fruit a capsule (as in ours) or a berry, the seeds often enclosed by a fleshy aril.

94 genera and 1,300 species chiefly of the tropics, somewhat fewer in temperate regions; 6 genera and 8 species in TX (with the removal of Forsellesia to Glossopetalon in the Crossomataceae); 1 species here.

The family is important chiefly for cultivated ornamentals in Euonymus and medicinal members of Maytenus (Mabberley 1987).

Shrubs or small trees; branchlets green, 4-sided. Leaves opposite, serrulate. Flowers perfect, small, in open axillary pedunculate cymes or solitary. Sepals basally united into a short, flat cup. Petals apically rounded, spreading. Staminal disk flat, 4- or 5-angled, adherent to the calyx and more or less adhering to and concealing the ovary; style short or obsolete. Fruit a loculicidal capsule with 3 to 5 lobes and as many valves. Seeds 1 to 4 per locule, each with a red aril.

177 species of the N. temperate zone, especially Aust.; 2 in TX; 1 here.

Some species are useful for wood, dye properties, etc. The species that Americans are familiar with are generally cultivated plants with colorful fruit and/or fall color (Mabberley 1987). Some species, including ours, have toxic or cathartic properties, though serious poisonings are known only from the fruit of E. europaeus (Lampe 1985).

1. E. atropurpureus Jacq. (Eastern) Wahoo, Burning-bush. Shrub or small tree, erect, 2 to 4(8) m tall; bark gray; branchlets greenish. Petioles 1 to 2 cm long; blades oblong-oval to elliptic, lance-ovate, or lanceolate, 5 to 13 cm long, acute to acuminate or attenuate, basally acute, finely serrulate, the upper surface glabrous, lower surface persistently finely pubescent or glabrous; stipules linear, to 1 mm long, quickly deciduous. Cymes pedunculate, axillary, 7- to 15-flowered; flowers dark red to purplish or tinged with green, 4-merous, generally 6 to 8 mm broad. Calyx lobes 1 to 1.5 mm long, often unequal; petals 3.3 to 3.8 mm long, 3.5 mm broad; disk 4-lobed; stamens nearly sessile; ovary generally 4-lobed unless with fewer lobes through abortion; style obsolete; ovules 2 per cell. Capsule usually deeply 4-lobed, smooth, red or yellowish-red, ca. 1.5 cm broad, dehiscing to show the red-arillate seeds; seeds brown or yellowish-brown, 6 to 7(8.5) mm long, 4 to 5 mm in diameter, smooth. Moist rich woods, bluffs, ravines, thickets, etc. Primarily in N. Cen. TX, in our area known at least from Old River Ranch in Burleson Co.; Ont. to MT, S. to NC, TN, AL, AR, OK, and TX, apparently excluding SC and LA. Apr.-July.

Two varieties in TX:

var. atropurpureus Blades ovate-elliptic, acute to abruptly short-acuminate, persistently pubescent below, especially on the veins. This appears to be the variety represented by our Burleson Co. material.

var. cheatumii Lundell Blades lanceolate, apex long-attenuate, both surfaces entirely glabrous.

The bark and fruit are cathartic and may be emetic, though the bark was once used medicinally (Lampe 1985).

Shrubs or trees, deciduous or usually evergreen. Leaves alternate, simple, petiolate, usually stipulate, margins entire to toothed or spiny. Plants usually polygamo-dioecious (mostly dioecious and with a few perfect flowers). Flowers regular, hypogynous, 4-(to 8-)merous, sessile or pedicellate, in axillary fasciculate, cymose, or racemose arrangements or sometimes solitary. Calyx small, sepals united, free of ovary, persistent, the lobes imbricate. Corolla white or tinged with green, deciduous, the petals free or basally united, imbricate. Stamens usually as many as and alternate with the petals and sometimes adnate to the corolla, all fertile in staminate flowers, anthers introrse; staminodia present in the pistillate flowers, about as large as the fertile stamens. Ovary sessile, superior, with 2 to 6(rarely more) united carpels and as many locules, style short or obsolete, ovules 1(2) per locule; ovary in male flowers rudimentary, sterile. Fruit drupe-like, with as many stones as carpels. Stones smooth to ribbed or striate, usually with 1 suspended seed, seed coat thin, endosperm abundant.

4 genera and 420 species nearly worldwide; 1 genus and 11 species in TX; 4 species known from our area.

The family is important in the U.S. primarily for cultivated ornamental shrubs and trees, but it also includes some taxa valued for their wood (Mabberley 1987).

Characters as described for the family, more precisely as follows: Stipules minute, deciduous. Plants generally fully dioecious or with a few occasional perfect flowers. Flowers axillary, in cymes, fascicles, or solitary, usually pedicellate. Calyx 4- to 9-parted. Corolla rotate, petals 4 to 9, elliptic to oblong, free or basally united. Stamens as many as the petals and alternate with them, epipetalous. Ovary subcylindrical, usually with 2 to 8 cells, style usually none, stigmas as many as the cells, separate or confluent. Fruit topped with the persistent stigma(s), usually with 4 to 8 1-seeded stones.

About 400 species worldwide, especially tropical and temperate Amer. and Asia; 11 in TX; 4 here. A useful reference for descriptions and county records is the work of Lundell (1943).

Many are cultivated for ornament, both deciduous and evergreen, and with some cultivars bred for showy fruit. I. aquifolium is the traditional English holly used as a Christmas decoration; in America this usually replaced by I. opaca. The wood of many is white and can be used in inlay, for musical instruments, etc. The leaves of some, for example I. cassine and I. paraguariensis, are high in caffeine and have been used in teas (Mabberley 1987). The fruits of some are regarded as toxic, causing vomiting and diarrhea if eaten (Lampe 1985).

1. Leaves thin-textured, deciduous; inflorescences sessile, all the flowers solitary or

fasciculate; pedicels lacking bractlets .....................................................................................2

1. Leaves coriaceous, evergreen; inflorescences pedunculate, the flowers in cymes or solitary; pedicels with bractlets at the base ..............................................................................3

The fruits are eaten by songbirds and gamebirds, while deer browse the young growth (Elias 1980).

Our plants differ from the typical variety in having shorter pedicels, denser pubescence, and smaller leaves. The species as a whole from TX and FL N. to TN and NC.

Sometimes grown for ornament and the foliage and fruit used for Christmas decorations. The wood, though white, turns brown with age and the trees are too small to be of use for large objects. Songbirds and gamebirds eat the fruit (Elias 1980).

The author has seen colonies of Atta carpenter ants carrying away the fruits. Songbirds and some gamebirds eat the fruit. The wood is white and hard but not very useful as the trees are small (Elias 1980). Sometimes cultivated as a shrub in local landscapes, with weeping, yellow-fruited, and dwarf forms available (Bailey, et al. 1976). The latter take well to shearing. The leaves are high in caffeine and were used in a ceremonial tea-like drink by Native Americans. The specific epithet "vomitoria" refers to the belief (probably erroneous) that the plant was used in purging ceremonies. The leaves, however, are not toxic (Tull 1987), though the berries are (Lampe 1985). Tan and gray dyes can be made from the leaves and yellows from the berries (Tull 1987).

Herbs, shrubs, or trees, some (not ours) true vines or stem succulents, very diverse in overall morphology. Leaves alternate, opposite, or whorled, simple to pinnately or palmately lobed or compound, commonly stipulate, but stipules often small, caducous, or represented by glands or membranes. Herbage glabrous to pubescent with various sorts of hairs or scales, sometimes stinging, some genera with milky or colored latex. Inflorescence quite variable, but flowers always unisexual, plants monoecious or dioecious. Non-Euphorbia type flowers: variously arranged, regular, perianth reduced to showy, of 1 or 2 whorls, the whorls similar or different. Nectary disk often present, at least in pistillate flowers. Stamens (1-)5 to many, free or variously connate. Gynoecium typically of 3 united carpels (occasionally 2 or 4 to many), typically 3-celled (except in, e.g., some Croton); styles 3 and distinct or united below and branched above, each branch often further divided, ovules 1 to 2 per locule, apical-axile, pendulous. Euphorbia-type flowers: very reduced, borne in cyathia which resemble single flowers, each cyathium cup-shaped, with one pedicellate female flower consisting only of a tricarpellate gynoecium as described above; staminate flowers represented by single pedicellate stamens, sometimes subtended by rudimentary bracts, rim of cyathium with nectary glands, each often with a petaloid appendage. Fruit usually a capsule or schizocarp (achene or utricle in some Croton), the dorsal carpel walls separating from the central axis or columella; seeds often with a caruncle or outgrowth around the micropyle.

Mabberley (1987) lists 321 genera and 7,950 species of cosmopolitan distribution (except the Arctic); in TX 20 genera and 137 species; 9 genera and 43 species locally.

The family is important for several crops. Natural rubber is obtained from the sap of Hevea brasiliensis trees. Manihot esculenta is the source of the staple foods manihot, cassava, and tapioca. Ricinus communis is the source of castor oil--and one of the most deadly poisons, ricin. Other genera supply medicinal or industrial oils, dyes, timber, or fruit. Many species are poisonous or have irritating latex. There are many ornamentals in the family, including species of Croton, Acalypha, Euphorbia, Codiaeum, and others (Mabberley 1987).

About 125 species of tropical and warm regions; 1 species escaping cultivation and naturalized in Texas.

1. S. sebiferum (L.) Roxb. (= Triadica sebifera (L.) Small) Chinese Tallow Tree. Fast-growing medium-sized tree to 15 m; trunk often crooked, branches spreading or drooping; bark smooth and reddish on younger wood, grayish-brown and widely-fissured on older trunks; wood brittle; sap milky. Leaves alternate, resembling those of Populus, blades rhombic to rhombic-ovate, widest at or below the middle, 3 to 8(9) cm long, apically acuminate to denticulate, basally rounded to acute or sometimes nearly truncate, with 2 small gland at the base of the blade, margin entire but slightly undulate; petioles longer than blades, slender; stipules subulate, caducous. Flowers in terminal thyrses (3)5 to 15 cm long, the bractlet of each node with 2 persistent, bulbous-glandular bractlets. Staminate flowers in clusters in the upper portion of the inflorescence, pedicel ca. 1 mm long; calyx ca. 1 mm broad, cup-shaped and irregularly 3-toothed; stamens 2; corolla, glands, and rudimentary ovary absent. Pistillate flowers few and solitary at the lower nodes of the inflorescence, sepals 3, triangular, nearly distinct; corolla, glands, and nectary disk absent; gynoecium 3-celled, subglobose, styles 3, free and spreading for about half their length, entire, the free portion brown and ventrally papillate. Fruit a 3-lobed capsule 1.2 to 1.8 cm long, dark brown, the outer walls readily falling; seeds 3, 7 to 8 mm long, more or less ellipsoid with one flat side, waxy white, long-persistent on the columella. Native to China and Japan; introduced as a shade tree and now escaping and persisting on the coastal plain from SC to TX; completely naturalized in some places. Common near houses, in vacant lots, old homesites, and so on, especially near water--along streams, around ponds, in moist thickets, etc. Flowering about May or June. Fall color ranging from yellow to orange, red, and maroon--sometimes all on one tree. Long treated in Sapium, now treated by some in Triadica.

The waxy covering of the seeds can be made into candles or used in soap, and a drying oil can be pressed from the seeds (Tull 1987; Mabberley 1987). The sap, leaves, and fruit wall are poisonous and the sap can cause dermatitis; the seeds should also be considered potentially toxic. Yellow-green dye can be made from the leaves (Tull 1987). This tree provides outstanding fall color in our area and is especially impressive when the white seeds persist against dark red foliage. However, the trees are very weak-wooded and susceptible to rot, making them short-lived in the landscape and prone to drop branches or split. The seeds can also be messy. These traits, combined with a general weediness, put this plant near the top of many people's list of "trash trees".

About 50 to 75 species of tropical America, rarer northward; 1 species in Texas.

1. C. texanus (Muell.- Arg.) Small Bull Nettle, Mala Mujer. Perennial herb from a stout root to 1 m long and 20 cm thick; stems several from the base, branched below or above ground, 3 to 5(10) dm tall, plant to 1 m broad; sap milky; herbage covered with white-based stinging hairs. Leaves alternate, orbicular in overall outline, deeply palmately 3- or 5-lobed and veined, lobes entire and ovate or acuminate to angled, sinuate-dentate, or shallowly lobed; petiole from longer than to shorter than the blade, with inconspicuous brownish-white glands 2 to 3 mm broad at the junction of the petiole and upper surface of the blade; stipules inconspicuous and commonly deciduous, 3 to 4 mm long, deeply 3- or 4-toothed or in some plants only one tooth developed. Plants monoecious; inflorescence pedunculate, cymose, terminal (sometimes exceeded by lateral axillary branches), well-branched but few-flowered, branches dichotomous toward the ends, determinate, the single truly terminal flower pistillate (or in some cymes apparently absent), ultimate branchlets each bearing a staminate flower subtended by 1 to 3 tiny subulate bracts. Staminate flowers fragrant, buds clavellate, 13 to 19 mm long; perianth of 1 whorl, petaloid, white, showy, with scattered stinging hairs, funnelform-salverform with a tube 15 to 20 mm long, longer than the 5(4) more or less oblong lobes; stamens 10(rarely 9?), included, in 2 whorls, the inner ones connate into a column, the outer free to their villous bases. Pistillate flowers with a single whitish, petaloid perianth whorl, 10 to 17 mm long, 5-lobed to near the base, with scattered stinging hairs; ovary oblong-obovoid, slightly 3-lobed, 3-celled, densely beset with stinging hairs and also hirtellous above; styles 3, briefly connate below, about 3 times dichotomous, ultimate ends slender. Capsule oblong, 15 to 20 mm long, hispid; columella white, persistent, with 3 narrow wings; seeds 3, 14 to 18 mm long, rounded-oblong, apiculate, smooth, brownish-white, caruncle prominent, sagittate, yellowish-white, 3 to 4 mm long. In sandy soils, common where the ground disturbed. Nearly throughout TX; also LA, OK, AR and S. into Mex. Flowering April-Nov.

The sap is toxic and caustic, but the main threat is from the vicious stinging hairs, which are capable of penetrating even denim. Some people also experience an allergic reaction to the sting (Tull 1987). If one can get to them, however, the seeds are edible and reported to be tasty. One wonders who was first curious--or desperate--enough to discover this.

Ours perennial or annual herbs (elsewhere also shrubs and trees), quite variable in habit; plants glabrous to variously pubescent; sap milky and acrid. Leaves alternate or opposite, in our species simple, entire to serrate or serrulate; stipules well-developed to reduced and scale- or gland-like. Flowers in ours all Euphorbia-type: unisexual, borne in cyathia which resemble individual flowers. Glands of cyathia 1 or more, rotund to cupped or horned; petaloid appendages present or absent, usually greenish, white, or pinkish. Staminate flowers variable in number per cyathium, each consisting of 1 pedicellate stamen. Pistillate flowers 1 per cyathium, often long-exserted, commonly nodding in age, consisting of a pedicellate tricarpellate gynoecium; styles 3, usually bifid but sometimes entire. Fruit a 3-celled, 3-seeded schizocarp-like capsule, each of the carpels falling from the persistent central axis (columella) and soon or tardily releasing the single seed. Seeds often carunculate, variously shaped and decorated.

One of the largest genera of flowering plants, with ca. 1,600 species worldwide, especially in warmer areas. Hatch, et al. (1990) listed 63 species for TX; 18 of which can be expected in our area. The genus includes taxa formerly treated in Chamaesyce, Tithymalus, Poinsettia, and others. Some current authors recognize Chamaesyce as a separate, valid genus and synonyms are provide for those who chose to recognize the split. This treatment is based, in part, on still-useful information presented by Norton (1900) and Wheeler (1941).

The genus has many important members. Most familiar is E. pulcherrima, the Poinsettia. Many African species are succulent and/or spiny, resembling cacti, and a number are cultivated as pot plants, including E. obesa and E. tirucalli. E. splendens is the popular Crown of Thorns. The sap of all species is poisonous and may cause allergic skin reactions. Some species with medicinal properties have been used in emetics, purgatives, depilatories, and so on. Some species are weedy, notably E. peplus in Europe and E. nutans, E. hypericifolia, E. marginata, and E. prostrata in our area. A few species have hydrocarbon chemistries of their sap which allow their use in waxes, waterproofings, rubber, etc. E. antisyphilitica, Candelilla, has a white waxy covering which can be refined for use in chewing gum and cosmetics. A very few species (none of ours!) have edible shoots (e.g. E. balsamifera of the E. hemisphere) (Mabberley 1987).

NOTE: Many TX species are rather weedy; several species not currently known from our area may someday be found here. E. glyptosperma, E. stictospora, and E. albomarginata may be keyed and are described in the Manual of Vascular Plants of Texas (Correll & Johnston 1970). E. humistrata may also make its way here. It is very similar to E. maculata, but roots at the lower nodes and has slender styles 0.5 to 0.7 mm long (cf. E. maculata's clavate styles which are 0.3 to 0.4 mm long).

1. Glands of cyathia without appendages; leaves alternate or opposite, blades essentially bilaterally symmetrical (at least on main stem) .......................................................................2

1. Glands of cyathia with petaloid appendages, OR if appendages absent then leaves all opposite and asymmetrical (with oblique bases) ....................................................................7

2(1) Glands deeply cupped, 1 to 3 per cyathium; cyathia clustered at the ends of the stems and branches, not in a 3-to several-rayed, branched inflorescence; leaves alternate or

opposite .....................................................................................................................................3

2. Glands flat or convex, 4 or 5 per cyathium; leaves alternate on main stem, whorled beneath the symmetrical 3-rayed inflorescence (pleiochasium), and opposite at the forks of the inflorescence branches ..................................................................................................4

This plant is occasionally cultivated for its rather showy bracts.

See NOTE at E. texana, below.

NOTE: According to Mark Mayfield (pers. comm 1995), even when found growing with E. spathulata, there are no intermediate forms.

Our plants represent a rather large eastern disjunct from the normal range (W. of Austin). In Grimes Co., it grows in association with other plants typical of the Edwards Plateau.

This species is one whose highly caustic sap can cause severe dermatitis or conjunctivitis in sensitive persons. It is very similar to E. marginata, Snow-on-the-Mountain, which has broader leaves and bracts (ca. 2 to 4 times longer than wide) and less pubescent capsules. That species is more or less the western counterpart of E. bicolor and is often cultivated for its showy bracts. Our species, too, has some ornamental potential.

The Plains Indians used this plant in medicines as a laxative, as a treatment for rheumatism, and in vermifuge preparations. It was used in Anglo-American folk remedies as an emetic (Kindscher 1992.).

For years and in many sources, this plant has been listed as E. chamaesyce L., a name which properly belongs to an Old World plant.

For many years the name E. maculata was erroneously applied to this species, and it was published as such in multiple places (e.g. Steyermark 1963). It has also been listed under Chamaesyce hyssopifolia (L.) Small, but E. hyssopifolia is a different species.

This plant is reported to be poisonous, especially to livestock (GPFA 1986).

geyeri) Geyer Euphorbia, Geyer's Spurge. Taprooted annual; stems 6 to 25 per plant, prostrate, 5 to 45 cm long, 0.4 to 1.4 mm thick; herbage glabrous. Leaves opposite, oblong to ovate-oblong or elliptic-oblong, 4 to 12 mm long and ca. 1/2 as wide, apex obtuse or emarginate, sometimes mucronate, base obtuse or rounded, oblique, margins entire; petioles 1 to 2 mm long; stipules free or those on the lower side of the stem sometimes united, 1 to 1.5 mm long, with (2)3(5) filiform segments. Cyathia solitary in the upper forks or apparently clustered due to shortened distal internodes, turbinate to broadly campanulate, 0.9 to 1.5 mm long; glands 4, often reddish, broadly oval to suborbicular, 0.2 to 0.4(1.6) mm long; petaloid appendages white to reddish, from 1/2 to 2 times longer than the glands are wide, entire to erose; staminate flowers 5 to 15(27) per cyathium, filaments and anthers pale, whitish to pale yellowish; pedicel of pistillate flower exserted, reflexed in age; styles 3, 0.2 to 0.3(0.5) mm long, usually erect and more or less rigid, bifid 1/3 to 1/2 their length, the divisions terete to subclavate. Capsule ovoid-triangular, 1.5 to 2 mm long and to 2.5 mm broad, angles sharp to narrowly rounded; columella 1.7 to 1.8 mm long; seeds plumply ovoid, acute, 1.3 to 1.4(1.6) mm long, 1 mm broad, light reddish-brown to nearly white, surface smooth, caruncle none. Sandy soils of Plains Country, S. and W. to Ward, Winkler, and Crane Cos., rarely E. to N. Cen. TX. Known from deep sandy soil in Milam Co. near Gause (which represents a bit of a range extension) and so possibly present in the neighboring W. portion of our area. WI, MN, IA, ND, and MT, S. to TX and NM. Late spring or summer-fall; the Milam Co. collection from Oct.

This plant is very similar to and perhaps best treated as an inland race of the coastal E. ammanioides H.B.K. (a name which might have priority should the two species be merged). According to some, however, the correct name for E. ammanioides (and thus a composite species) is E. bombensis Jacq.

Perennial herbs with stems from a woody crown, sap milky. Herbage glabrous. Leaves alternate, ascending, glandular-serrulate or -crenulate, nearly sessile; stipules reduced and glandlike. Flowers unisexual, in compact, spike-like panicles with pistillate flowers below and staminate flowers above, each flower subtended by a bract and 2 larger gland-like stipules. Staminate flowers short-pediceled, solitary or clustered, calyx cup-like and obscurely 2-lobed; corolla and disk absent; stamens 2. Pistillate flowers with a 3-lobed calyx; corolla and disk absent; gynoecium subglobose, 3-celled, 3-ovulate, lower portion (gynobase) becoming indurate and persistent; styles 3, simple. Capsule shallowly 3-lobed, the upper portion separating from the gynobase and dehiscing loculicidally and septicidally; columella fragile and readily breaking off. Seeds with a prominent caruncle.

About 30 species of tropical and warm America, Malaysia, Madagascar, and Fiji; 3 in TX; 1 here.

1. S. sylvatica L. Queen's Delight. Stems 3 to 6(8) dm tall. Leaves variable in shape, narrowly elliptic to lanceolate or oblanceolate, (3)4 to 7(10) times longer than broad, (2)3.5 to 7(12) cm long, apex and base acute, margin serrulate or crenulate, with a small, deciduous gland in each notch (less often the glands on the margin); petiole 1 to 7 mm long; stipules reduced and glandlike. Staminate flowers in many-flowered, bracted cymules on the upper portion of the inflorescence, calyx cup-like, 1 to 2 mm long, obscurely and unevenly 2-lobed; stamens 2. Pistillate flowers: calyx deeply 3-lobed, lobes 0.7 to 2 mm long, with 1 lobe oriented toward the inflorescence axis and the other 2 facing away; styles 4 to 5 mm long. Capsule broadly oblong, plumply and distinctly 3-lobed, ca. 12 mm long, green, very hard, the indurate gynobase triangular, thick and horny or woody, with 3 lobes ca. 6 mm long; columella ca. 8 mm long, triangular, stout but brittle and usually soon lost, leaving a short triangular peg on the gynobase; seeds 3, ovate-oblong, ca. 8 mm long excluding the caruncle, light gray-brown, smooth (or faintly wrinkled); caruncle subreniform, ca. 4 to 5 mm broad and 2 to 2.5 mm tall, pointed, whitish to light tan. Usually in loose sandy soil in open areas. Frequent in most of the state E. of the Trans Pecos; VA to FL, W. to TX, KS, and NM. Spring-early summer, our specimens in flower mostly from Apr. [S. salicifolia (Torr.) Rydb.].

Mabberley (1987) states that the "rhizomes" are used medicinally, but does not give specific uses.

Ours annual or perennial herbs (elsewhere also shrubs and trees), branches persistent or deciduous, if deciduous the leaves on the main axes reduced to scales. Leaves spirally arranged or distichous, simple, entire, short-petiolate; stipules persistent or deciduous. Plants monoecious or dioecious, flowers usually axillary, solitary or in cymules. Sepals in ours 5 or 6, united at least partially. Corolla none. Disk usually present. Staminate flowers: disk usually dissected or lobed; stamens 2 to 6, free or united, pollen quite variable across the genus. Pistillate flowers: sessile or pedicellate, carpels in our species 3; styles free or united, variously bifid and/or dilated. Fruit a 3-locular capsule, ours elastically dehiscent. Seeds 2 per locule, in our species shaped like an orange segment, seed coat dry, variously ornamented, embryo straight to curved, endosperm abundant.

At least 750 species, the majority tropical, a few temperate; 7 species recorded from TX (1 introduced); 4 known from our area. This treatment owes much to the work of Webster (1970).

A few species (not ours) have medicinal properties, edible fruit, or ornamental value (Mabberley 1987).

A second variety, var. riograndensis Webster, is confined to the lower Rio Grande Valley.

Ours annual or perennial herbs (elsewhere also shrubs), usually with stellate hairs or peltate scales on at least some parts of the plants. Leaves alternate (sometimes seeming opposite or whorled beneath the inflorescence), simple, entire to serrate, petiolate; stipules present, often small and deciduous. Plants monoecious or dioecious, flowers in axillary or terminal spikes or racemes, in monoecious plants the spikes with pistillate flowers below and staminate above. Staminate flowers: calyx deeply or shallowly (4-)5-(6-) lobed; petals absent or as many as and alternate with the calyx lobes; lobed disk often present when petals absent; stamens 5 or more, usually 10 to 20 in TX material; rudimentary ovary absent or very poorly developed. Pistillate flowers: calyx with 5 or 6(to 9) deep or shallow lobes, valvate in bud; corolla absent or petals as many as and alternate with the calyx lobes; lobed disk sometimes present, usually present when corolla none; ovary (1- or 2-)3-celled; styles (1)2 or 3, each once or more dichotomous. Capsule (1-or 2-)3-celled; seeds 1 per cell, carunculate.

At least 800 species of the tropics and subtropics; 22 species in TX; 8 here.

NOTE: The above figures reflect the inclusion of the two species formerly in Crotonopsis. Webster (1992) makes the valid point that the Crotonopsis, with its single-celled and -seeded fruits, fits easily within Croton and represents the final stage in the reduction series which begins with tricarpellate fruits and continues through the bicarpellate, single-seeded fruits of Croton monanthogynus. Both species of Crotonopsis required completely new names upon removal to Croton because the epithets available for them were already in use in Croton.

Several species have value as medicines, teas, timbers, etc. (Mabberley 1987). Of our local species, C. monanthogynus and C. texensis can be used as teas, though C. texensis is toxic and has been used medicinally (Tull 1987).

1. Stems and leaves with silvery scales, most conspicuous on the undersides of the leaves ..2

1. Stems and leaves glabrous to stellate pubescent, not silvery-scaly ......................................4

See NOTE following C. willdenowii, below.

NOTE: Apparently much more common in our area than C. michauxii and possibly our only species of single-seeded, silvery Croton. Grady Webster has examined local material and returned them all as C. wildenowii, although some specimens may appear to be intermediate between the two species in some respects. Webster (1995) points out that the two species are very similar and that there may be problems with species delineation.

Three intergrading varieties are found in Texas.

Our plants seem to be all or nearly all var. septentrionalis Muell. -Arg. with plants usually more than 25 cm tall; larger leaves commonly longer than 3 cm; pubescence variable but the central process of each hair not more than 6 times as long as the radii; petiolar gland 0.5 to 0.8 mm broad, seeds oblong. PA, IN, IA, and NE, S. to FL and TX. [C. glandulosus L. var. angustifolius Muell. Arg.]

Var. lindheimeri Muell.- Arg. is smaller, 10 to 20 cm tall, and has larger leaves about 2.5 cm long, central portion of each hair generally shorter than the radii, petiolar gland 0.1 to 0.4 mm broad. Found to our S. and W. Not listed for our area, but some of our plants seem to be on the small side and have smaller leaves than is typical for var. septentrionalis; it is possible there is some influence from var. lindheimeri.

A tea can be made from the dried leaves, though care must be taken not to confuse this plant with similar, toxic species and to watch for possible allergic reactions (Tull 1987). Tan colors can be obtained on wool using the whole plant as a dyestuff (Tull 1987).

A second variety, var. tharpii M. C. Johnst., occurs in TX in the Trans-Pecos and the S. part of Plains Country and W. Edwards Plateau. It has long, acute leaves, pubescence rough or shaggy rather than velvety, an fruiting pedicels erect. It is not expected to occur in our area.

As described above, our plants are probably all var. lindheimeri (Engelm. & Gray) Muell. -Arg. [C. capitatus Michx. var. albinoides (Ferg.) Shinners; C. engelmannii Ferg. and var. albinoides Ferg; C. muelleri Coult. and var. albinoides (Ferg.) Croizat.]

The other variety, var. capitatus, has blunt, uniformly long-petioled leaves and orbicular, unmottled seeds. Found in far N. Cen. TX, it is not expected to be found in our area.

The seeds are often carried away by ants, which relish the nutrient-rich caruncle. Some people seem to be allergic to the pollen.

Native Americans used this plant in medicinal preparations to treat a variety of ailments including stomach pains, kidney disorders, and snakebite. It was also an ingredient in a Zuni treatment (apparently effective) for syphilis (Kindscher 1992.) However, the plant has toxic properties and is reportedly used in insecticidal preparations (Kindscher 1992; Tull 1987).

Annual or perennial herbs (as ours) or subshrubs. Stems decumbent to erect, simple to branched. Leaves alternate, petiolated, variously shaped, entire to crenate or serrate; stipules small, lanceolate. Plants monoecious (as ours) or dioecious, flowers usually in axillary and/or terminal spikes (rarely paniculate), staminate and pistillate flowers occupying various relative positions, clusters of flowers subtended by bracts. Staminate flowers: several to many in each bract, bracts (in ours) inconspicuous and lanceolate; sepals 4; valvate; corolla none; disk none; stamens 4 to 8(16), free or basally united, anther sacs often becoming twisted in age. Pistillate flowers: one or two per bract, bracts variously lobed, often foliaceous, commonly enlarging as the fruits mature; sepals 3(to 5); corolla none; disk none; carpels (2)3, styles 3, distinct, the main branches usually divided several times, in some species pink or reddish. Capsule usually 3-celled, ovules 1 per cell. Seeds ovoid, carunculate, variously tuberculate or pitted, brown to black or mottled.

About 390 to 430 species of temperate to tropical regions of both hemispheres; 10 species in TX; 5 in our area (including some which are debatably distint.)

A few species are cultivated for ornament; A. wilkesiana Muell. Arg. (Copperleaf, Jacob's Coat, Beefsteak Plant) is grown for its leaves which are mottled green, bronze, red, scarlet, white, etc. (Mabberley 1987).

The case can be made that A. monococca is only a variety of A. gracilens--the two are quite similar and are certainly closely related. This is the approach adopted by Kartesz (1998). However, the uniformly 1-seeded fruits and the larger, ridged (as opposed to pitted) seeds make A. monococca readily distinguishable from A. gracilens.

Two varieties have traditionally been recognized: var. gracilens, with leaves lanceolate to linear-lanceolate, margins crenate, and staminate portion of spike usually not exceeding the pistillate bracts, and var. delzii L. Mill., with leaves linear, entire to slightly crenate, and staminate portion of spike usually far exceeding the pistillate bracts. Many of our plants are readily separable. However, the traits that distinguish var. delzii vary clinally rather than abruptly and plants with the characters of var. delzii are found outside the TX-W. LA range generally given for the variety. There is debate, then, whether varieties should be recognized (Levin 1995). Dr. Geoffrey Levin is exploring whether, among other possibilities, the "var. delzii" plants represent introgression of A. monococca into A. gracilens.

NOTE: Very closely related and similar to A. rhomboidea Raf. There have even been some problems with typification of these species. The characters usually used to separate the two--leaf shape, stem pubescence, and petiole length--are inconsistent. Cooperrider (1984) cited this as a reason for combining the two and reducing A. rhomboidea to a variety of A. virginica, an approach adopted by Kartesz (1998). However, Levin (1995) notes that features of the pistillate bracts are diagnostic and that, even though the two often grow together, there is no evidence that hybridization occurs--thus his preference for recognizing two species.

See NOTE at A. virginica, above.

Perennial herbs, ours from woody rootstocks. Stems erect to ascending or trailing. Herbage glabrous or commonly with malpighiaceous (attached in the middle and free at both ends) hairs. Leaves alternate, usually with 3 prominent nerves from the base, entire or serrate. Plants monoecious or dioecious, ours monoecious with flowers in long or short bracted axillary racemes with 1 to 3 pistillate flowers at the base and staminate flowers above. Staminate flowers: sepals 5, valvate; petals 5, in ours free of the staminal column; glands 5, free or fused to the staminal column; stamens 7 to 10 in 2 whorls, monadelphous; staminodia sometimes present. Pistillate flowers: sepals 5, imbricate, accrescent and enlarged in fruit; petals 0 to 5, well developed or reduced; glands 5, opposite the sepals and inserted on the ovary disk; ovary subglobose, 3-celled, triovulate, styles 3, free or briefly united basally (as in TX material), bifid, glabrous or pubescent above. Fruit a schizocarpic capsule, splitting first into 3 1-seeded cocci, the columella persistent. Seeds ovoid to subglobose, caruncle none, surface variously decorated.

Depending upon interpretation, 17 to 50 species, primarily of warm and temperate America; TX material 6 species in the subgenus Ditaxis; 2 species here.

1. Inflorescences longer than or about equalling the leaves; leaves sessile or subsessile ........

Var. pilosissima (Benth.) Shinners, endemic to the Ed. Plat. and S. Rio Grande Plains, has glands of the flowers pubescent.

Var. laevis (Torr.) Shinners, which occurs in W. Cen. TX and the Trans Pecos, is entirely glabrous and somewhat succulent.

Perennial herbs, some species suffrutescent. Stems 1 to several from the base, erect to decumbent or trailing or twining, simple or branched. All TX material with herbage and inflorescence with stinging hairs mixed with softer spreading pubescence. Leaves alternate, sessile to petiolate, blades cordate or ovate to lanceolate or linear, entire to serrate, toothed, or lobed; stipules usually persistent, lanceolate to ovate, acute to attenuate, entire and ciliate. Inflorescences racemose, apparently opposite the upper leaves (actually terminal but surpassed by the shoot in the axil of the subtending leaf); lower 1 or 2 flowers pistillate and the remaining ones staminate, each flower subtended by a lanceolate bract. Calyx lobes 3 to 6(7). Corolla and disk absent. Staminate flowers: bracts pubescent, entire; flowers pedicellate, the pedicel with an abscission zone below the middle, the basal portion persistent; stamens 2 to 6 (to 10 in terminal flowers). Pistillate flowers: bracts ciliate, entire or 3-lobed; flowers pedicellate, the pedicel with an abscission zone below the middle but the entire pedicel and columella persistent; ovary usually tricarpellate, subglobose, with sparse to dense stinging hairs; styles 3, spreading or recurved, smooth to papillate. Fruit a capsule, 3-seeded and explosively dehiscent (in one species sometimes 1-seeded, winged, and indehiscent); columella with 3 apical interlocular points. Seeds 1 per locule, without caruncle, smooth or slightly rough, more or less globose.

About 125-150 species of tropical, subtropical, and warm temperate regions; 10 species in TX; 3 in our area.

Contact with the stinging hairs produces an itching, burning sensation similar to that caused by nettles, but the irritation seldom lasts longer than a few hours. Identification is easiest when both flowers and fruit are present.

Shrubs, trees, or woody vines, sometimes with thorns. Leaves alternate or opposite, deciduous, typically with prominent pinnate venation, petiolate; stipules minute and early deciduous. Flowers perfect or unisexual, in cymes, thyrses, or umbels or sometimes solitary or appearing glomerulate on short shoots, perigynous (sometimes appearing epigynous at anthesis when a nectary disk obscures the ovary), generally small and not showy, usually greenish or yellowish. Hypanthium campanulate or hemispherical. Sepals (4)5, deltoid, attached to the rim of the floral cup. Petals (4)5, clawed or spatulate, often cucullate (hooded), sometimes absent. Stamens (4)5, opposite the petals and alternate with the sepals, inserted on the margin of the disk, often enclosed by the hooded petals. Disk usually present either near the rim of the hypanthium, lining it, or nearly filling it and hiding the ovary but not adhering to the ovary or adherent only to the basal portion. Ovary superior, 1- to 4-celled, ovules 1 per cell, basal; style 1. Fruit usually drupe-like, with 1 to 3 stones, or else a schizocarp-like capsule.

58 genera and ca. 875 species worldwide, especially in the tropics an subtropics; 9 genera and 22 species in TX; 3 genera and 4 species here.

The family is important for medicinal plants in several genera, a few dye and timber plants, and a few cultivated ornamentals. Ziziphus jujuba (jujube) has edible fruits (Mabberley 1987).

NOTE: Ziziphus jujuba is known to persist in cultivation, but it is not currently known to do so in our area. Z. obtusifolia (T. & G.) Gray is common in TX but no collections from this region are known to the author. Should either jujube be found, it may be recognized by having axillary spines or thorn-tipped branches, and 3-stoned, juicy fruits.

12 species from E. Afr. to E. Asia; 1 in N. Amer.

1. B. scandens (Hill) K. Koch. Alabama Supple-jack. Unarmed woody vine to ca. 20 m. Stems glabrous, twining, young growth reddish brown and lustrous, older stems darker, often to nearly black. Leaves alternate, with slender petioles; blades ovate to elliptic, (2)3 to 8 cm long, apically rounded to obtuse-apiculate, basally rounded, margin entire or obscurely crenate or undulate, surfaces glabrous, conspicuously pinnately veined, the under surface paler and the veins commonly slightly pinkish. Inflorescences small panicles or thryses at the ends of the lateral branches, usually equalled or surpassed by the foliage. Flowers perfect or unisexual, greenish, small, ca. 2 mm broad, 5-merous. Hypanthium and disk small and free of but enclosing the ovary; sepals ovate-triangular, acute to acuminate; petals equalling the sepals, obovate, without claws, hooded; stamens equalling or shorter than the petals; style short. Fruit ellipsoidal, 5 to 8 mm long, blue-black and glaucous; stone 2-celled and 1- or 2-seeded. Woods and margins of woods. E., SE., N. Cen. and S. Cen. TX, W. to ravines in the S. part of the Ed. Plat.; VA to MO, S. to FL and TX; also Mex. and Guat. Flowering in spring.

The stems can be used for wickerwork and baskets. This plant is capable of girdling trees, and it is not uncommon to see an unsupported corkscrew of living rattan remaining where the original support tree has long since died and decayed. Tull (1987) reports a yellow dye from the stems and leaves; the berries are known to stain and might also be tried. This is not the rattan used for furniture--that is the stem of a tropical climbing palm.

Shrubs or small trees, unarmed or some branches spine-tipped. Leaves alternate or opposite, unlobed, entire to serrate, usually glabrous or nearly so; stipules small and deciduous. Plants dioecious, polygamodioecious (with both perfect and unisexual flowers), or with all perfect flowers; flowers solitary in the axils or in pedunculate axillary cymes. Hypanthium and staminal disk small, free of the ovary. Sepals 4 or 5. Petals (0)4 or 5, short-clawed, apically notched and with the sides enfolding the stamens. Stamens 4 or 5, inserted on the disk. Ovary 2- to 4-celled, sunken into but free of the disk. Fruit a berry-like drupe with 2 to 4 1-seeded stones.

125 species of the N. hemisphere to Brazil and S. Afr.; 4 in TX; 1 here.

Several species are grown as ornamentals; others are dye sources or have medicinal uses (Mabberley 1987).

1. R. caroliniana Walt. Carolina Buckthorn, Indian Cherry, Yellow-wood, Polecat Tree. Large shrub or small tree to 6(12) m, crown rounded and open; trunk usually branched near the ground; bark light gray and smooth to shallowly furrowed; branchlets reddish and pubescent when young, becoming glabrous and gray. Leaves ovate to elliptic or narrowly obovate, 5 to 14 cm long, 2 to 4(7) cm broad, acute to obtuse or acuminate, tapered to rounded basally, entire to remotely crenate or with a few teeth, dark yellow green and glabrous above, paler below and glabrous to sparsely pubescent, the pinnate veins conspicuous, yellow below; petioles glabrous to puberulent, 8 to 18 mm long. Inflorescences in ours in few-flowered axillary clusters, peduncles and pedicels pubescent. Flowers small, perfect, 5-merous; calyx campanulate, 3 to 4 mm long, lobes lanceolate, about as long as the tube; petals shorter than the calyx; stamens included. Fruits black at maturity, obovoid to subglobose, 7 to 10 mm in diameter, with 2 to 4 stones. Bottomland woods. E. and SE. TX, W. along watercourses to N. Cen. and S. Cen. TX; VA to NE, S. to FL and TX. Late spring to summer. Treated by Kartesz (1998) as Frangula caroliniana (Walt.) Gray .

The fruits are eaten by birds, including woodpeckers, while deer browse the young foliage (Elias 1980). Humans can eat the fruit too, though care should be taken with identification as the fruits of other species have toxic or cathartic properties (Lampe,1985). The berries can be used to produce dark brown colors on wool (Tull 1987).

Shrubs, sometimes weak and nearly suffrutescent, armed or unarmed, deciduous or evergreen. Leaves opposite or alternate, with 1 to 3 veins from the base, commonly serrate, the teeth gland-tipped. Inflorescences axillary or terminal umbels or panicles, often rather showy as the calyx is white as well as the corolla. Calyx 5-parted, the lower portion adnate to the disk and ovary, the lobes incurved and deciduous. Petals 5, long-clawed, cucullate. Stamens 5, free, exserted. Ovary 3-(4-)celled, style 3-lobed. Fruit a septicidal and partially loculicidal capsule, separating into 3, 1-seeded parts which fall from the accrescent, persistent floral cup and staminal disk.

55 species of N. Amer., especially the W. portion; 4 in TX; 2 here.

Some species are cultivated for their flowers, which in some are blue (Mabberley 1987).

The dried leaves were used as a tea substitute by the American colonists during the Revolutionary War. The roots have astringent properties and have been used in medicines (Tull, 1987). Native American tribes used the roots to treat bowel troubles, snakebite, and colds, and made various teas from the leaves (Kindscher, 1992).

Woody vines or viny shrubs, some (not ours) shrubs, climbing by tendrils, sometimes tendrils tipped with adhesive disks. Leaves alternate, simple or compound; stipules deciduous. Inflorescences at the nodes, opposite the leaves, paniculate or cymose. Flowers commonly unisexual and perfect on the same plant, usually many, small, regular, usually greenish, more or less perigynous and often with a ring- or cup-shaped disk, ours 4- or 5-merous. Calyx very small, the lobes essentially obsolete. Petals valvate, in some genera, e.g. Vitis, more or less apically united and falling at anthesis. Stamens opposite the petals, abortive in the pistillate flowers; anthers introrse. Ovary superior, usually bicarpellate and bilocular, style 1. Fruit a 1- or 2-locular berry, each locule usually with 2 seeds. Seeds deeply grooved, bony.

13 genera and ca. 800 species, mostly of tropical and subtropical regions; 4 genera and 17 species in TX; 4 genera and 11 species here.

The family includes many cultivated ornamentals, notably in Cissus, Parthenocissus, and Ampelopsis. Grapes belong to the genus Vitis (Mabberley 1987).

Climbing or scrambling woody vines with tendrils, in some species the tendrils with adhesive disks. Leaves petiolate, palmately compound, thin-textured (as opposed to succulent in Cissus), leaflets usually 3 to 7, coarsely serrate. Inflorescence cymose or a panicle of cymes; flowers perfect or unisexual. Calyx small, with 5 tiny lobes. Petals (4)5, free, reflexed or spreading, thick, concave, expanding before falling. Disk indistinct or absent. Stamens (4)5, opposite the petals. Ovary 2-celled, ovules 2 per cell. Fruit a thin-fleshed berry with 1 to 4 seeds.

About 10 species of temperate N. Amer. and Asia; 3 in TX; 1 here.

Several species are cultivated ornamental vines, including P. tricuspidata, Boston Ivy, and our own P. quinquefolia (Bailey 1976; Mabberley 1987).

1. P. quinquefolia (L.) Planch. Virginia Creeper, Hiedra, Parra. Climbing or scrambling vine, tendrils 3- to 8-branched, with adhesive disks at the tips, sometimes with aerial roots; old stems brown, slightly roughened, lenticels visible, younger branchlets red to green or brown, slightly flattened. Leaves petiolate, with (3)5(7) leaflets, leaflets petiolulate, elliptic to obovate or oblong-obovate, to ca. 15 cm long and 5 cm broad, the central one the largest, apically acuminate, basally usually cuneate, coarsely toothed at least in the upper half, upper surface dull green and glabrous, lower surface paler and glabrous or occasionally pubescent. Inflorescences terminal and from the axils of the upper leaves or opposite the upper leaves, forming a panicle of cymes with a well-defined central axis, glabrous, with 25 to 200 flowers. Petals 5, 2 to 3 mm long, yellowish green; disk small or indistinct, adnate to the ovary; stamens 5. Berries black to dark blue, globose, 5 to 8 mm in diameter; seeds 1 to 3(4), obovoid, 3.5 to 4 mm long, shiny brown. Woods, rocky banks or slopes, wood edges, and fencerows. E. 1/2 TX; ME, OH, and SD, S. to FL and TX. May-July. Fall foliage color red. [Includes var. hirsuta (Donn) Fern.; P. hirsuta (Donn) Small; Psedera hirsuta (Donn) Greene; Psedera quinquefolia (L.) Greene].

A number of horticultural varieties have been described (Vines 1960). Several sources (e.g. Tull 1987; GPFA 1986) report that the berries are poisonous or that the plants have dangerously high levels of oxalic acid, but Lampe (1985) lists the plant as merely having irritant raphides (calcium oxalate crystals). The stems can be used in basketry (Tull 1987).

Woody vines or viny shrubs, ours all deciduous, climbing with simple or branched tendrils. Bark usually loose in age, exfoliating in shreds and without or with only inconspicuous lenticels, pith brown, interrupted at the nodes by paler diaphragms (one local species, V. rotundifolia, with tight, non-exfoliating bark and no nodal diaphragms). Leaves simple, usually more or less cordate in overall outline, entire to deeply palmately 3- or 5-lobed, margins usually dentate or serrate, apex obtuse to acuminate, base typically cordate with a broad sinus, pubescence various; stipules promptly deciduous. Flowers in compound thyrses produced opposite the leaves, flowers minute, fragrant, mostly 5-merous, pedicellate, mostly functionally unisexual and plants functionally polygamo-dioecious. Calyx minute and reduced, represented by a collar at the base of the flower. Corolla of (3)5(9) petals, 1 to 3 mm long, united apically, separating at the base, deciduous as a unit at anthesis. Stamens (3)5(9), filaments erect and 2 to 7 mm long in staminate flowers, reflexed or absent in pistillate flowers. Intrastaminal nectary disk of 5 more or less separate glands alternate with the stamens. Pistil 0.5 to 2 mm long, with 2(3 or 4) locules, ovules 2 per locule; style short and stigma capitate. Fruit a juicy berry with 1 to 4 seeds. Seeds pyriform to obovoid, the ventral surface with 2 longitudinal grooves, the dorsal with 1 broader groove.

About 65 species of the N. hemisphere; 11 in TX; 7 to be expected here. An invaluable reference is Moore (1991). (The reader is referred to this very complete source for grapes encountered outside the strict local area.

Though many species have edible fruit and are made into wine, V. vinifera, originally from SW Asia, is the typical wine and champagne grape. There are hundreds of cultivars, many of which involve hybridization with American species such as V. labrusca. Most European wine grapes are now grown on clonal American rootstocks which are resistant to the phylloxera insect. V. labrusca includes the common cultivars 'Concord' and 'Catawba'. Raisins and sultanas are the dried fruits of some grape varieties; some of these are sometimes called currants but are not to be confused with true currants, which are Ribes (Bailey, 1976; Mabberley 1987). Some species are grown as ornamentals, often on arbors; some have colored foliage (Bailey 1976). The stems of many are useful for "wicker" work or basketry (Tull 1987). Our local species are all important wildlife foods.

NOTE: For positive identification, it is helpful to have mature leaves, young growing tips, and flower or fruit. It is often necessary to split the stems lengthwise to examine the nodal pith--this is much easier to do before drying.

The fruits are edible, the pulp sweet but the skin rather tough and astringent. The juice makes good jam, jelly, and wine. The "Scuppernong" variety has silvery-amber fruits. Few natural hybrids are known, except with the other variety of the species, var. munsoniana (Simpson ex Munson) M. O. Moore [=V. munsoniana Simpson ex Munson], which occurs in FL, FA, and AL (Vines 1960).

The fruit is edible, with a sweet pulp but an astringent, rather irritating skin. Often used in making wine. Natural hybrids are reported with V. cinerea, V. vulpina, V. aestivalis, and others. Artificial hybrids have been made with V. vinifera (Vines 1960).

Two varieties possible here; a third is not found in TX.

var. aestivalis Summer Grape, Pigeon Grape, Bunch Grape. Leaf undersurfaces moderately to densely glaucous, variously arachnoid pubescent; nodes usually not glaucous; pith diaphragms more than 2 mm broad; berries 9 to 14 mm in diameter. E. 1/3 TX; MA to SE. IA, MO, E. OK, E. TX, and FL.

The berries vary in taste and quality from dry and astringent to juicy and sweet--and then good for wine and jelly. They are eaten by many birds and mammals, including turkey and deer. Several horticultural varieties have been developed (Vines 1960).

var. lincecumii (Buckl.) Munson Post Oak Grape, Pinewoods Grape. Similar to the typical variety, but the current season's branchlets more or less densely tomentose; pith diaphragms usually less than 2 mm broad; stipules less than 1.5 mm long; leaves quite commonly 3- to 5-lobed; berries usually more than 14 mm in diameter, heavily glaucous; seeds 7 to 8 mm long. Flowering a little earlier and somewhat more drought tolerant. Usually on well-drained upland sites--sandy open woods, scrub, thickets, etc. E. and S. Cen. TX, W. to Bastrop Co.; also W. LA. Vines (1960) included in the range OK and AR, E to MI, N. to IN, and MO. Definitely present in our area, in fact, probably more common than var. aestivalis. [V. lincecumii Buckl.; originally misspelled "linsecomii" and sometimes appearing so in print.].

Hybrids are known with V. cinerea, V. rupestris, V. vulpina, V. mustangensis, etc. (Vines 1960).

Four varieties; both TX varieties possible in our area.

var. cinerea Current season's branchlets with short, straight hairs, occasionally with arachnoid pubescence also; leaves usually more than 10 cm long, moderately arachnoid pubescent and/or hirtellous below; berries scarcely if at all glaucous. Low, often wooded sites. S. IA, S. IL, and S. IN, S. to E. KS, E. OK, and E. TX; a few locations also in AL and FL. Definitely present in our area. [Includes var. canescens (Engelm.) Bailey ex Gray; V. aestivalis Michx. var. canescens Engelm. or Engelm in Gray].

Said to hybridize with V. aestivalis, V. vulpina, V. rupestris, V. mustangensis, etc. The fruit is eaten by many species of birds and mammals (Vines 1960).

var. helleri (Bailey) M. O. Moore Heller Grape. Similar to above, but with the berries moderately to densely glaucous; current season's branchlets usually without hirtellous pubescence and not as strongly angled; leaf blades usually less than 10 cm long, the undersides only sparsely hirtellous or sometimes glabrate. In TX, most common on the Ed. Plat, but also in the Cross Timbers and Prairies and in the Blackland Prairies. [V. berlandieri Planch.; V. cinerea (Engelm. in Gray) Engelm. ex Millard var. berlandieri (Planch) Comeaux; V. cordifolia Lam. var. helleri Bailey; V. helleri (Bailey) Small].

Reported to hybridize with V. mustangensis, V. rupestris, etc. (Vines 1960).

Said to hybridize with V. rupestris, V. vulpina, V. aestivalis, V. cinerea, etc. (Vines 1960).

This species has been used extensively as a rootstock in Europe. Known hybrids include crosses with V. aestivalis, V. mustangensis, V. cinerea, V. riparia, V. rotundifolia, etc. The fruit is eaten by birds and mammals and is suitable for jellies and wine (Vines 1960).

About 350 species, mostly in the tropics but some subtropical; we have the 1 species found in TX.

The genus includes several species grown as houseplants--C. quadrangula, C. rhombifolia, etc.--which are often called Treebine, Kangaroo Treebine, and so forth (Bailey, et al. 1976).

1. C. trifoliata (L.) L. Cow-itch, Marine Ivy, (Ivy) Treebine; Hierba del Buey. Vine from a tuberous root; stems stout, climbing or scrambling, to 10 m long or more; older stems tight-barked, warty; young branchlets usually 6-ridged, becoming more or less quadrangular, lenticels obvious, orange-red and becoming warty; tendrils without adhesive disk tips; pith white, uninterrupted; foliage rather unpleasantly scented when bruised. Leaves deciduous or semi-evergreen, succulent and fleshy, somewhat rubbery, to 8 cm long, quite variable in shape, from simple and broadly ovate or ovate-reniform to 3-lobed or trifoliolate with obovate to ovate, cuneate leaflets, margins coarsely and irregularly toothed. Peduncles usually longer than the leaves below; inflorescences umbelliform cymes, axillary or sometimes appearing terminal if in the axil of the uppermost leaf. Flowers perfect or unisexual, regular, 4-merous. Calyx campanulate, with 4 lobes; petals greenish, free, spreading, slightly cucullate (hooded); stamens opposite the petals; disk 4-lobed, cup-shaped, free of the ovary except at the base. Pedicels recurved in fruit; berry obovoid, black, 6 to 9 mm long, beaked by the persistent style, flesh dry; seeds 1 to 4, trigonous-obovoid, 2-grooved apically, 5 to 7 mm long, brownish. Climbing or sprawling on rocks or vegetation of open woods, chaparral, salt marshes, railroad grades, etc. Throughout much of TX, rare in the extreme E. and the Panhandle; MO & KS, S. to FL, TX, and Mex. Flowering May-Sept. [C. incisa of authors but not (Nutt.) Des Moul.; Sicyos trifoliatus L.].

Climbing vines or erect viney shrubs. Bark tight, not exfoliating, lenticels prominent. Pith white, uninterrupted. Tendrils sometimes present opposite the leaves. Leaves deciduous, thin-textured, simple or pinnately compound. Inflorescence a dichotomously branched cyme; flowers small, greenish, usually 5-merous and perfect. Calyx saucer-shaped, the lobes usually rudimentary. Petals distinct, spreading. Nectary disk cup-shaped, free of the ovary except at the bottom, entire to slightly crenate; stigma capitate. Fruit a pulpy or sometimes dry berry with 1 to several trigonous-obovoid seeds.

About 20 species of temperate and subtropical America; 2 in TX; both here.

A few species are cultivated as ornamental climbers (Mabberley 1987).

The berries are visually appealing but are definitely not palatable. Tull (1987) reports colorfast gold and brown dyes from this plant.

The berries are not edible by humans, but a number of birds do eat them (Vines 1960). This plant strongly resembles a grapevine, but the cymose rather than truly paniculate inflorescence, tight bark, and uninterrupted pith provide clues to its identity.

Ours perennial or annual herbs. Leaves simple, alternate, opposite, or occasionally whorled; stipules in ours represented by glands at the base of the petiole or absent. Inflorescence racemose or cymose; flowers perfect, regular. Sepals (4)5, imbricate. Petals (4)5, free or rarely basally united, convolute in bud, usually falling quickly, yellow, blue, or white. Stamens 5, alternate with the petals; staminodia sometimes present and alternate with the stamens. Ovary superior, of 2 to 5 united carpels, placentation axile or apical-axile, locules 2 to 5 or sometimes twice as many due to the presence of false septa, or sometimes the partitions not reaching the apex and the ovary unilocular (usually not so in ours); ovules 2 per carpel; styles as many as the carpels, free or united; stigmas slender to capitate. Fruit in ours a septicidal capsule; seeds flat and oily.

15 genera and ca. 300 species worldwide; 1 genus and 21 species in TX; 7 here.

The family is most important for flax, Linum usitatissimum (see below).

As described for the family. Leaves mostly alternate or opposite, essentially sessile in ours; stipular glands when present visible as dark dots on either side of the leaf bases. Flowers 5-merous. Ovary 5-carpellate, the fruit separating into 5, 2-seeded segments or 10, 1-seeded segments.

About 20 species of temperate and subtropic regions, especially the Mediterranean; 21 species in TX; 7 in our immediate area. A major reference for our plants is Rogers (1984). His previous articles are also useful (Rogers 1964a, 1964b, and 1968).

Some species are cultivated for ornamentals; L. usitatissimum is flax (Mabberley 1987). Many yellow-flowered species have synonyms in Cathartolinum (Rogers 1984).

NOTE: For confident identification, specimens should have flowers at anthesis and some mature, dehiscing fruit. It is easiest to see any fusion of the styles on immature fruit as even united styles can be torn apart lengthwise when the fruit dehisces.

1. Flowers blue (rarely white) .......................................................................................................2

1. Flowers yellow ..........................................................................................................................3

2(1) Inner sepals with ciliolate margins; petals 10 to 15 mm long; styles 3 to 6 mm long

This plant is the source of linen fibers. The oil (known as linseed oil) from the seeds has many uses in paints, varnishes, soap, etc., while the seed meal is used in cattle feed (Mabberley 1987).

The typical variety is not found in Texas.

NOTE: L. hudsonioides Planch is very similar and occurs just outside our area, usually to the south and west, but with at least one population to our southeast. (e.g., Waller Co.). It can be distinguished by, among other characters, a lack of hirsute pubescence in the upper portions. On the slim chance that it is one day found in our region, the reader is referred to Rogers (1984) for a complete description and a discussion of the differences between the two species.

Rather similar to L. rigidum Pursh. var. rigidum, which differs in having solid yellow flowers and no stipular glands. This is a plant primarily from N. TX, (Rogers 1964b). There is a slight chance it may someday show up in the northern part of Leon Co.

Herbs (as ours), elsewhere also shrubs, trees, and vines. Leaves alternate, opposite, or whorled; stipules none. Flowers usually irregular. Sepals 5, sometimes dissimilar. Petals 3 to 5, commonly united, often adnate to the stamens, often crested. Stamens 3 to 7 or 4+4 or 10, usually united basally. Ovary superior, of 2 to 5(8) united carpels, placentation usually axile, ovules 1 per cell. Fruit various. Seeds arillate and/or hairy.

18 genera and 950 species nearly worldwide but absent from the W. Pacific; 1 genus with 27 species in TX; 1 genus with 6 species here.

Ours annual or perennial herbs. Leaves alternate, opposite, or whorled, simple and entire, sessile or with a very short petiole. Flowers in axillary or terminal racemes, subsessile to pedicellate, strongly irregular, often subtended by small bracts. Sepals 5, the uppermost and the lower 2 small, greenish, but the lateral 2 larger, petaloid and termed wings, deciduous. Petals usually 3, united at the base, the lowermost, the keel, boat-shaped and with a central portion or lamella, clawed, sometimes 3-lobed, usually with an apical crest or beak, but sometimes unappendaged; 2 upper petals ligulate to ovate, sometimes galeate, united to the keel and/or the stamen tube at least basally; 2 lateral petals rarely present and if so, minute. Stamens (6)8, united by the filaments into a sheath split on the upper side, the tube adnate to the keel and upper petals at the base, anthers dehiscent by apical or apical/ introrse pores. Ovary 2-celled, with 1 pendulous ovule per cell; style usually long and slender, often bent, stigma 2 lobed, often one lobe tufted. Capsule 2-celled, equally or unequally so, marginless, margined, or winged, flattened perpendicular to the septum. Seeds usually pubescent and nearly always arillate, globose to conic or fusiform.

About 500-550 species nearly worldwide; 27 in TX; 6 here.

Some are cultivated ornamentals and some are used medicinally in various regions (Mabberley 1987).

1. Flowers white or greenish; racemes dense and sharp-pointed ..............................................1

1. Flowers some shade of pink or purple, rarely white; racemes usually apically blunt (if pointed, then flowers definitely NOT white) .............................................................................3

This plant was used by the Seneca tribe to treat snakebite. It was used by various Native American tribes in remedies for coughs, colds, and other ills, and by European settlers in various medicinal preparations (Kindscher 1992).

Several varieties have been described, though Hatch, et al. (1990) list none. As treated here, includes var. isocycla Fern. and var. sphenostachya Penn. Some of our plants may be referable to var. ambigua (Nutt.) Wood with the upper leaves alternate and the stem not much branched. This taxon is recognized by Kartesz (1998) as P. ambigua Nutt.

Some sources recognize varieties.

A monogeneric family.

Perennial herbs or small shrubs, sometimes highly-branched and somewhat thorny. Herbage often gray pubescent. Leaves alternate, narrow, entire, sessile or short-petiolate, estipulate. Flowers perfect, irregular, borne in the axils of the upper leaves, each pedicel usually with 2 leafy bracts. Sepals 4 or 5, unequal. Petals 5, the upper 3 long-clawed, free or partially united, usually reddish or purple, the 2 lower petals smaller, thick, sessile, usually greenish and glandlike. Stamens 4, free or united to the claw of the uppermost petal, each anther cell dehiscent by an apical pore. Ovary superior, 1-celled, with 2 pendulous ovules. Fruit 1-seeded, indehiscent, the surface covered with prickles. Seeds apparently without endosperm.

An American genus with 15 species; 4 in TX; 1 here.

This family has historically been treated as part of the Fabaceae (Caesalpinioideae) or as part of the genus Polygala in the Polygalaceae, but it is now treated as a separate family.

1. K. lanceolata Torr. Trailing Ratany, Krameria, Crameria. Perennial herb from a dark, woody, usually branched rootstock; stems decumbent, prostrate, or trailing, 1 to 18 dm long; herbage silky-strigose. Leaves linear, linear-elliptic, or occasionally elliptic-oblong, 6 to 20 mm long, acute or commonly apiculate with a small brown point. Pedicels 0.5 to 3 cm long, pubescent. Sepals 4 or 5, free, ovate-lanceolate, 8 to 10 mm long, pubescent, showy, usually maroonish; 3 upper petals free, red-purple or maroon, the other 2 petals thick, sessile, greenish, and gland-like; stamens 4; ovary conspicuously densely pubescent. Fruit globose or very broadly ovate, 6 to 9 mm in diameter, densely woolly, armed with a number of straight prickles 2 to 4 mm long, these often at first maroon-tinted. Sandy prairies, roadsides, hillsides, etc. Present in much of TX except the Pineywoods region; KS to AZ, S. to TX and Mex. Spring-fall, our collections Apr.-July. [K. secundiflora DC.].

Trees, shrubs, or vines. Leaves alternate (in ours), simple, ternate, or pinnately compound, stipules present or absent. Plants dioecious and/or with perfect flowers, flowers usually regular, in ours in racemes, panicles, or cymes. Sepals 4 or 5 sometimes united basally. Petals, in ours, 4 or 5, often with basal scales or glands. Disk usually present around or bearing the stamens. Stamens usually more than the petals, in ours usually 8 to 10 in 2 series, filaments often hairy. Ovary typically tricarpellate (sometimes with fewer or more carpels) and multilocular; styles free or united; ovules 1 to several per locule. Fruit fleshy or dry, indehiscent or dehiscent, in ours a berry or inflated capsule. Seeds sometimes arillate or with fleshy outgrowths.

144 genera and 1,325 species, chiefly in tropical and subtropical regions, a few in the temperate zone; 6 genera and 9 species in TX; 3 genera and 3 species here.

The family is important for some edible tropical fruit including Litchi, some oilseed crops, and some cultivated ornamentals. Many members contain toxic saponins (Mabberley 1987).

Primarily climbing herbs with tendrils. Leaves bi-ternate to variously decompound, the leaflets entire to incised. Flowers small, whitish or yellowish, in axillary corymbose or racemose-paniculate clusters, each inflorescence pedunculate and with 2 tendrils below the flowers. Sepals 4 or 5, the 2 outer smaller than the inner. Petals 4. Stamens 8. Fruit a thin-textured, inflated, 3-lobed, 3-celled capsule.

14 species, mostly of the tropics, and especially common in the W. hemisphere; 3 in TX; 1 here.

The seeds of some, especially the tropical C. grandiflorum, have been used as beads (Mabberley 1987).

1. C. halicacabum L. Common Balloon Vine, Parolitos. Annual herbaceous vine; stems several-ribbed, wiry, with axillary tendrils; herbage sparsely pilose to subglabrous. Leaves ternate or biternate, leaflets to ca. 8 cm long and 3 cm broad, ovate-lanceolate to rhombic-lanceolate or narrowly lanceolate, acuminate, toothed or incised-lobed, base decumbent on the petiole. Inflorescence umbelliform, branches ca. 1 cm long. Flowers irregular, ca. 4 mm long; sepals 4; petals 4, whitish, obovate, often somewhat unequal, each with a basal petaloid appendage; stamens 8; nectary disk outside the filaments. Fruit 3 to 4.5 cm broad, inflated, 3-lobed, 3-locular; seeds 3, black, ca. 5 mm in diameter. Trailing or sprawling on the ground or climbing over surrounding vegetation, usually in open or brushy waste places, sometimes on river banks, usually in moist soil. NE., Cen., and S. TX; widespread in warmer regions, NJ to PA, OH, MO, and KS, S. to FL and TX; also Mex. and tropical Amer. Jun.-Nov.

Popping the balloons has some recreational value for the young-at-heart.

About 13 species of tropical and warmer parts of the world. We have the one species and variety found in TX.

The berries have a high saponin content and some are used as soap substitutes. The seeds of some are used as beads, and some are cultivated ornamentals (Mabberley 1987). The fruits are poisonous, but serious intoxications are very uncommon and gastroenteritis is usually the worst result. The plants can produce contact dermatitis in sensitive individuals (Lampe 1985).

1. S. saponaria L. var. drummondii (Hook. & Arn.) L. Benson. Western Soapberry, Jaboncillo. Moderately slow-growing tree, usually less than 10 m tall, to 15 m under ideal conditions; bark gray to tan or reddish, in narrow scaly plates, wood yellow; young branchlets yellow-green, becoming gray, puberulent or glabrous. Leaves estipulate, petiolate, even-pinnate, leaflets 6 to 10 pairs, elliptic-lanceolate to narrowly lanceolate, entire, acuminate, falcate, to 10 cm long and 4 cm broad, the rachis very narrowly winged. Inflorescence a dense terminal panicle; flowers whitish, 4 to 5 mm broad, regular. Calyx deeply (4-)5-lobed, glabrate, margins ciliate; petals 4 or 5, obovate, with pilose claws, attached below the staminal disk, usually appendaged; stamens (7)8 or 10, filaments long-hairy, inserted on the disk. Fruit a globose berry ca. 1.3 cm in diameter, flesh yellowish, translucent; seed solitary, 8.5 to 9 mm long, black, appearing smooth but with minute pits. Often in groups on roadsides, streambanks, and fencerows, and in bottomland woods. Scattered throughout TX; KS to NM, S. to LA, TX, and Mex. Flowering Mar.-July; fruiting in fall. [S. drummondii H. & A.; S. marginatus Coult.].

The fruits are used in Mexico as laundry soap and in fish poisons. They can also be used to give a yellow dye on wool (Tull 1987). Sometimes planted as an ornamental.

A monotypic genus.

1. U. speciosa Endl. Mexican Buckeye, Texas Buckeye, Monilla. Shrub or small tree to a maximum of 10 m, usually smaller, trunk to 2 dm in diameter; bark thin, smooth, light gray to brown, on older trees shallowly fissured. Leaves estipulate, petiolate, odd-pinnately compound, leaflets 3 to 7, sessile or with short petiolules, ovate to ovate-lanceolate, to 12 cm long and 6 cm wide, acuminate, sometimes with an expanded and rounded tip, serrate at least distally, basally rounded to broadly obtuse, pubescent below when young, soon glabrate. Flowers appearing with or before the leaves, in lateral fascicles from axils of the previous season, blossoms pink to purplish pink, fragrant, irregular, bisexual or unisexual. Calyx deeply 5-lobed, sparsely pubescent; petals 4 or 5, obovate, to 1 cm long, the claws pilose and fimbriate-crested at the apex on the inner side; stamens 7 to 10, anthers cherry-red. Fruit a stipitate, woody, 3-celled, 3-lobed capsule, 3.5 to 5 cm broad, more or less wrinkly, green or suffused with red, gold to brown at dehiscence; seeds globose, 1 to 1.5 cm broad, lustrous dark brown to blackish with a large, pale hilum. Usually in rocky areas, usually associated with limestone or calcareous sandstone, in canyons, on slopes or ridges, often above water. S. Cen. and W. TX, E. to about Dallas Co.; in our area known from Old River Ranch and outcrops in Grimes Co.; TX and SE. NM; also adjacent Mex. Flowering Mar.-Jun., ours primarily Mar.-Apr.

Trees or shrubs. Leaves opposite, palmately compound, estipulate, leaflets with marked, straight, pinnate venation. Perfect and unisexual flowers often on the same plant, in terminal panicles or racemes, zygomorphic, showy. Sepals 5, fused at least basally. Petals (4)5, unequal, clawed, brightly colored or whitish. Nectary disk commonly present, often 1-sided. Stamens 5 +(0)1 to 3. Ovary superior, of (2)3(4) united carpels, with as many locules, style 1, stigma simple. Fruit a loculicidal capsule, leathery in ours, sometimes spiny, ovules 2 per locule, but usually only 1 seed maturing. Seeds relatively large, with a hard coat and large hilum; cotyledons unequal; endosperm none.

Two genera of the N. temperate zone to SE. Asia; 1 genus with 2 species in TX; we have both species.

Some taxa are cultivated for ornament or for timber (Mabberley 1987).

Deciduous shrubs and trees; bark more or less unpleasantly scented. Leaves petiolate, with 5 to 11 leaflets, leaflet margins serrate. Flowers largely without functional pistil and hence sterile; pedicels jointed. Calyx campanulate to tubular, somewhat irregular, commonly gibbous or oblique basally. Petals 4 or 5, unequal. Stamens 7 or sometimes 5, 6, or 8, filaments slender and often unequal, anthers glandular-apiculate. Ovary generally 3-celled unless with fewer cells by abortion.

13 species of Eur., Ind., E. Asia, and N. Amer.; 2 in TX, each with two varieties; one variety of each species locally.

All parts of the plants are poisonous, especially the twigs and seeds. There have been reported cases of human and livestock poisonings, though the seeds are edible if cooked and were eaten by Native Americans of California (GPFA 1986; Mabberley 1987). Because the seeds are toxic, they are not an important wildlife food (Elias 1980). Some species, including those of N. Amer., were used as fish poisons or in medicines to treat humans or horses (Tull 1987; Mabberley 1987). Interspecific and intervarietal hybrids exist; some of these and several of the species are cultivated for ornament (Mabberley 1987). The seeds are sometimes used like marbles by children (Mabberley 1987) or carried for luck.

NOTE: The following key is for our local area only; on the Ed. Plat. a yellow-flowered variety of A. pavia exists. Occasional hybrids of the two following species may be found. They are intermediate between the parents in floral coloration and leaflet size.

The other variety in Texas is var. flavescens (Sarg.) Correll, with yellow flowers and apparently confined to the Ed. Plat. Where the two are found together, intermediates occur.

The flowers are pollinated by hummingbirds (Wyatt & Lodwick 1981).

The eastern form, var. glabra (Ohio Buckeye) is found in the Pineywoods region and is not currently known from our area. It usually has 5 leaflets, only very rarely 6 or 7.

Trees or rarely shrubs; sap watery and sweet. Leaves opposite, simple, and palmately veined and/or lobed to palmately divided or compound, occasionally (as ours) pinnately compound; usually estipulate. Inflorescence terminal or lateral, corymbose, umbelliform, paniculate, or racemose; flowers regular, hypogynous or sometimes somewhat perigynous, usually both perfect and truly or functionally unisexual on the same plant or sometimes plants dioecious, . Sepals usually 5. Petals none or as many as the sepals. Stamens (3)8(12), inserted on or outside a nectary disk or disk rarely absent. Ovary superior, 2-carpellate, 2-celled, styles 1 or 2, stigmas 2, ovules usually 2 per locule. Fruit a winged schizocarp eventually separating into 2 1-seeded samaras. Seeds without endosperm.

2 genera and 113 species of N. temperate and tropical montane regions; 1 genus with 4 species in TX; 1 species here.

The family is important for the genus Acer, as described below.

Deciduous trees or shrubs. Flowers racemose, paniculate, or corymbose. Sepals (4)5(12), often colored, to some degree united. Corolla none or petals as many as the sepals, usually clawed, inserted on the rim of a perigynous or hypogynous disk. Stamens 3 to 12. Styles 2, united only below, stigmatic along their inner sides. Fruit the typical winged schizocarp.

111 species of temperate and tropical montane regions; 4 in TX; 1 here.

The genus is important for timber and wood for instruments and household items. A. saccharum is the sugar maple from which syrup and sugar are obtained. Many species are cultivated for shade and for fall color, which in some types is quite brilliant. A. palmatum is the Japanese maple, which is cultivated for its decorative foliage (Mabberley 1987).

NOTE: A. rubrum L., Red or Scarlet Maple, is common in swamps and alluvial woods in E. TX. It has simple, palmately lobed leaves with serrate margins and acute sinuses; the fruits are glabrous and commonly reddish when young. This species is not currently known from our area, but there is a slight possibility that it may be encountered in under-explored portions of E. Madison and Grimes Cos.

1. A. negundo L. Box-elder, Ash-leaved Maple, Arce, Fresno de Guajuco. Small deciduous tree to 15(20) m, trunk straight to crooked, branched near the ground, to a maximum of 1.2 m in diameter, usually smaller; bark of older trees thin, light brown to gray, with deep furrows and ridges separating into scales; young branchlets green and pubescent to glabrous, becoming gray. Leaves pinnately compound, leaflets 3 to 9, 5 to 10 cm long, 5 to 7.5 cm broad, petiolulate, papery and thin-textured, pubescent when young and pubescent or glabrate below in age, prominently veiny below, terminal leaflet elliptic to obovate or rhombic, apically toothed, the lateral leaflets narrower and with a few coarse teeth or lobes, leaves of fast-growing branch tips and sprouts with more and more-deeply lobed leaflets, on the whole the foliage strongly resembling poison ivy. Flowers produced with or just before the leaves, unisexual, greenish. Staminate flowers ca. 7 to 15, fasciculate and pendulous on slender pedicels. Pistillate flowers in racemes of ca. 4 to 9. Calyx 5-lobed; petals and disk none; male flowers with ca. 4 to 6 functional stamens. Samara mericarps 2.5 to 4 cm long, the wings divergent at an angle of 45 degrees or less, glabrous or pubescent, greenish to yellow or reddish; seed slightly less than 1/2 the length of the wing. River banks, low or floodplain woods, fencerows, and waste places. FL to TX, N. to NY, S. Ont., MN, Sask., and Man., W. to MT, WY, NE, KS, OK, and scattered in the mountain West; also Mex. and Cen. Amer. Apr.-May. Fall color not impressive.

Several varieties; 2 in TX; both possible here and intermediates not impossible.

var. negundo Young branchlets glabrous to slightly glaucous, green. E. Great Plains. Apparently the more common variety here.

var. texanum Pax Young branchlets velutinous; samara pubescent to glabrous. W. MO, E. KS., and southward.

The wood of this species is weak and not as useful as that of the other maples, but is suitable for crates, pulp, and firewood. It has been used as a street tree in the past, but the weak wood and messy fruits make it rather unsuitable. It is weedy in Europe where it has been introduced (Mabberley 1987).

Ours shrubs, woody vines, or occasionally small trees; bark and sometimes herbage with resin ducts; sap often resinous, milky, or acrid, in some species causing severe dermatitis. Leaves alternate (rarely opposite), trifoliolate to once pinnate (some, but not ours, with simple leaves), deciduous or evergreen; stipules usually absent or essentially so. Inflorescence a terminal thyrse, axillary panicle, or sometimes a cluster of spikes or catkins; flowers often subtended by bracts. Flowers many, small, (3- or 4-)5-merous, regular, usually hypogynous, appearing before or with the leaves, perfect or unisexual by abortion and the plants then monoecious or dioecious. Receptacle concave to convex, sometimes forming a gynophore, commonly developing into a ring- or cup-like disk. Perianth usually present, sometimes absent. Stamens as many as the petals and alternate with them, or sometimes twice as many or absent. Carpels 1 or 2 to 5, fused, but gynoecium in ours usually unilocular and uniovulate; styles separate or united. Fruit dry or drupe-like with a waxy or resinous mesocarp and bony or crustaceous endocarp. Seed with little or no endosperm.

About 73 genera and 850 species of tropical, subtropical, and Mediterranean regions and temperate N. Amer.; 5 genera and 14 species in TX; 3 genera and 7 species here, including one rarely-escaping cultivated species.

The family is economically important for the food crops mango (Mangifera), cashew (Anacardium), and pistachio (Pistacia). Some members, especially species of Toxicodendron (poison ivy and poison oak), have allergenic resins, while the resin or sap of others is used in tanning leather or in ink, lacquer, or dyes. A few taxa are cultivated for ornament, e.g. Pistacia (pistache) and Cotinus (Smoke Tree) (Mabberley 1987).

1. Plants true trees, persisting or rarely escaping cultivation; leaves even-pinnately

Shrubs or small trees, often forming thickets. Leaves alternate, ternate or once odd-pinnate, estipulate. Herbage without toxic resins, often aromatic when crushed. Plants polygamodioecious (usually dioecious but with some perfect flowers). Flowers yellow to greenish white, in terminal thyrses or panicles or terminal compounds spikes, appearing before or with the leaves, each flower subtended by one caducous lanceolate bract or one persistent deltoid bract and 2 bractlets. Sepals 5, united basally, persistent. Petals 5, free, imbricate in bud, spreading at anthesis. Fertile stamens 5, pistillate flowers with 5 to 10 vestigial stamens separated from the ovary by a flat, lobed disk. Ovary unilocular, style 3-parted apically. Fruit a red or reddish-yellow drupe, externally usually with glandular and hyaline hairs interspersed.

About 200 species of temperate and warm regions; 6 in TX; 4 here. As treated here and by Hatch, et al. (1990) and Kartesz (1998), excluding Toxicodendron. For a discussion of the segregation of Toxicodendron from Rhus, see Gillis (1971).

Several species are used in tanning and dyeing, e.g. R. coriaria with a 26% tannin content and the source of dye for Morocco leather. Wax and lacquer are obtained from others (Mabberley 1987). Lemonade-like drinks can be made from the fruit of local species, as can dyes ranging from tan to red-brown (Tull 1987). Native Americans used several species for their medicinal preparations, most having to do with astringent properties (Kindscher 1992). Species of Rhus (as treated here without Toxicodendron) do not produce contact dermatitis except in extremely sensitive individuals who respond to nearly all members of the family (Tull 1987). The common name may also be spelled or pronounced "Shumac" (among other variations).

1. Leaves ternate; flowers appearing with or before the leaves; floral bracts deltoid,

The stems are quite flexible and can be used in basketweaving. Native Americans of the Southwest used them for that purpose (Tull 1987), and the Cheyenne used the leaves in smoking mixtures and medicines (Kindscher 1992).

Several varieties exist; 3 are found in TX; 2 found locally; intermediate individuals or populations possible.

var. serotina (Greene) Rehd. Mature leaves pubescent below or mostly glabrous except for the bases of the leaflets and the rachis, terminal leaflet 2.5 to 6 cm long, flabelliform-ovate, more or less narrowed apically and variously crenate-lobed. Flowering before the leaves on some plants and with the leaves on others--often in the same population; floral bracts glabrous to densely pubescent, margins apically ciliate. Fruits densely longish-hairy; stone 3.8 to 4.8 mm long. Sandy woods, ravines, hillsides, etc. E. 1/2 TX; IL, IA, and SE. SD, S. to AR, TX. [R. trilobata var. serotina (Greene) Rehd; Schmaltzia serotina Greene; S. trilobata Greene var. serotina (Greene) Barkl.; R. nortonii (Greene) Rydb.].

var. flabelliformis Shinners Skunkbush. Mature leaves glabrous, terminal leaflet 15 to 33 mm long, cuneate-obovate, apically obtuse to nearly truncate, variously crenate to lobed. Flowering before or with the leaves; floral bracts glabrous or glabrate within an apically ciliate margin. Fruits densely longish-pubescent; stone 3.5 to 4.5 mm long. Rocky slopes, calcareous outcrops, prairies, mesquite plains, sandy woods, brushy ravines, etc. Cen. & W. TX; also S. OK. [R. trilobata of various authors and R. trilobata var. trilobata].

NOTE: Following Barkley (1937), some sources (e.g., Kartesz 1998) maintain R. trilobata and place this within it as R. trilobata Nutt. var. trilobata. However, since intermediates between varieties thus assigned to R. trilobata and those assigned to R. aromatica exist, it would seem logical that the group is perhaps best treated as a single species until relationships within the complex can be resolved. In that case, the name R. aromatica (1789) has priority over R. trilobata (1838).

This plant was used by many Plains tribes in medicinal preparations as a styptic, anti-hemorrhagic, and astringent. The leaves were also used in tobacco mixtures and the roots in yellow dyes (Kindscher 1992). A tart drink can be made from the fruits (Tull 1987).

Occasionally planted for fall color. The fruits can be used in drinks and dyes can be made from the plants (Tull 1987).

Native Americans used the fruits in drinks and the leaves in smoking mixtures (Powell 1988).

Ours woody vines, shrubs, or subshrubs, often rhizomatous, frequently climbing by aerial rootlets; resin in all parts of the plants capable of causing dermatitis. Leaves alternate, estipulate; leaflets 3(5 or 7), entire to toothed, undulate, or variously lobed, upper surface glabrous to sparsely pubescent, lower surface glabrous or scattered-strigose to densely pilose or velvety, sometimes the hairs in tufts in the axils of the veins. Inflorescence an axillary paniculate or racemose thyrse, pendent when large, ultimate clusters with 3 or 4 flowers. Plants dioecious, in section Toxicodendron (to which all of our species belong) flowers conservative in morphology within a sex rather than within a species. Sepals 5, united only briefly below, imbricate in bud, broadly lanceolate or ovate, green below and cream above, often with purple veins, shriveling but persistent in fruit. Petals 5, cream, free, imbricate in bud, ovate to lanceolate, obtuse, smaller in female than male. Fertile stamens 5, borne on a glandular disk attached to the ovary base, shriveling and persisting in fruit; sterile stamens present in female flowers. Gynoecium 3-carpellate but only one carpel fertile, ovary sessile or buried in the disk; style 1, 3-branched apically, stigmas capitate, ovule 1; rudimentary ovary present in male flowers. Fruit a globose to flattened drupe, with a brittle, chartaceous exocarp; waxy, fibrous mesocarp with resin canals visible as black striations; and bony endocarp permanently attached to the testa; fruits green until ripening to cream, yellow, straw-colored, or tan, glabrous, scabrous, papillose, or with eglandular hairs; exocarp commonly separating from the mesocarp and the mesocarp-endocarp-seed unit often referred to in literature as the "seed".

Six species of N. Amer. and Asia, some accidentally introduced elsewhere; 4 in TX; 2 here. (For a discussion of the segregation of Toxicodendron from Rhus, see Gillis (1971).)

Members of the genus produce allergic contact dermatitis. Long-chain catechols bind with skin proteins, and the body produces antibodies to the resulting compound. Upon further exposure, an antigen-antibody reaction occurs, resulting in swelling, itching, and blisters. A period of 12 to 48 hours can elapse between contact and expression of the rash. Usually only the contact site develops the rash, but sometimes previous exposure sites respond. Prevention is the best means of avoiding an episode--protective clothing and washing with lots of water (the toxins take about 10 minutes to penetrate skin). The toxins can also be contracted from contaminated clothes, pets, backpacks, etc. The pollen and smoke from burning plants can also be toxic. Topical steroids are useful in reducing the misery of the rash; antihistamines are not. Severe cases may require injections of steroids. True tolerance appears to exist in 15 to 30% of the population; in others, sensitization and subsequent reaction can occur at any age (Lampe 1985). Folk remedies abound, including rubbing the affected area with jewelweed (Impatiens), dock (Rumex), bleach, etc. (Tull 1987). Birds eat the fruit with impunity (Vines 1960).

NOTE: For keying purposes, it is best to use "sun" leaves from older branches as they are more constant and diagnostic than "shade" or juvenile foliage. Material from both sexes should be examined, if possible.

Kartesz (1998) uses the name T. pubescens P. Mill for this species. This name has been applied to several different plants, only one of which is the taxon in question. The type of the name is not this species, and no type of T. pubescens Mill is known. For a discussion, see Gillis (1971).

There are 9 subspecies, widely distributed from S. Can. to Guat., E. 1/3 U.S., Mex., Berm., Bahamas, Japan, W. and Cen. China, Taiwan, and Kurile and Sakhalin Islands; 5 subspecies in TX; apparently only 2 here as separated by the above key. Intergrades between subspecies do occur.

2a. subsp. radicans Leaflets usually entire or with 1 lobe (the terminal leaflet with 2), glabrate to scattered-strigose above, often with curly hairs near the base, lower surface with tufts of straw-colored or hyaline hairs (occasionally reddish-brown) in the axils of the major veins, blades 2.5 to 17 cm long, 2 to 13 cm broad, terminal leaflet basally obtuse, subcordate, or truncate, usually biggest below the center, petiolule 0.5 to 6 cm long; petiole 2 to 20 cm long. Fruits globose, 3 to 6.5 mm broad, puberulent, scabrous, or papillose (surface texture often visible only with strong magnification). Very common on roadsides, fencerows, railroad rights-of-way, and sand dunes and in disturbed woods, floodplain woods, and wet areas. Often associated with Parthenocissus, Ulmus, Fraxinus, Ampelopsis, and (in our area) Rubus. More or less throughout the state; N. S., S. to FL and the Bahamas, W. to VT, KS, AR, and TX. Flowering Apr.-May. [Rhus radicans L. and var. vulgaris forma intercursa Fern.; R. toxicodendron L. var. radicans Eaton and var. vulgaris Michx., etc.].

2b. subsp. pubens (Engelm. ex S. Wats.) Gillis Leaflets ovate, serrate, notched, or sometimes one-lobed (the terminal leaflet sometimes with 2), upper surface scabrous or rarely glabrous, often with a line of curly hairs on the midrib, lower surface densely strigose, hirsute, or velutinous with erect hairs, velvety to the touch, without tufts of hair in the axils, veins usually slightly raised, terminal leaflet 3 to 20 cm long, 3 to 11 cm broad, acuminate, petiolule 0.3 to 5 cm long; petiole 2 to 13 cm long, hispid, villous, or tomentose. Fruit glabrous, often glaucescent, rarely with minute papillae or hairs, 3 to 4.5 mm broad. Often weedy or in ruderal areas, usually in SE evergreen forests, associated with Quercus virginiana, Ulmus crassifolia, or Liquidambar styraciflua; present in our area. Distribution in the former Eocene Gulf Embayment: NW. MI, SE AR, and E. LA; scattered NE. to TN, KY, and MO, NW. to OK and possibly KS, W. to TX. Flowering in mid to late spring. [Rhus toxicodendron L. var. pubens Engelm. ex Watson; R. toxicodendron L. var multifolia Vines].

Trees or shrubs. Leaves alternate, once or twice pinnately compound or some (not ours) simple, estipulate. Inflorescence various, in ours paniculate. Flowers in ours perfect (in others unisexual or plant polygamous), regular. Sepals (2)3 to 5(7), imbricate in bud. Petals 3 to 7(14), sometimes in 2 whorls, imbricate, valvate, or convolute. Stamens 7 to 14 in 1 or 2 series, generally monadelphous with the anthers sessile on the stamen tube. Nectary usually present as a ring around the ovary. Ovary superior, of (1)2 to 6(20) united carpels with as many locules, placentation usually axile, with 1 to many ovules per cell; style and stigma 1. Fruit capsular or drupe-like.

51 genera and 575 species primarily of the tropics, a few in the subtropics; 1 species naturalized in TX and present in our area.

The family is important for timber trees in several genera. Swietenia is mahogany. There has recently been much interest in natural insecticides from the Neem tree (Azadirachta) (Mabberley 1987).

3 species of the Old World tropics; one escaping cultivation and naturalized in TX.

1. M. azedarach L. Chinaberry, Pride of India, Canelón, Paraíso. Tree to ca. 15 m, crown broad and rounded; bark gray or brown, fissured; wood rather weak; young branches with conspicuous lenticels. Leaves petiolate, twice odd-pinnately compound, 30 cm or more long, sometimes quite large; leaflets many, ovate to elliptic or lanceolate, basally rounded, apically acute or more often acuminate, crenate-dentate to incised or lobed, to 6 cm long and 3 cm broad. Flowers many per panicle, fragrant; pedicels ca. 3 mm long, minutely pubescent with simple or stellate hairs. Sepals usually 5 or 6, 1 to 2 mm long, elliptic, pubescent like the pedicels; petals 5 or 6, narrowly oblanceolate to spatulate, obtuse to acute, ca. 1 cm long, pale lavender or whitish, spreading; stamens 10 to 12, united by the filaments into a dark purplish tube 8 to 10 mm long, the orifice with numerous short, slender filaments outside and 10 to 12 anthers inside. Fruit drupe-like, pale golden or yellow, subglobose, becoming wrinkly with age, ca. 1.5 cm broad, the flesh thin, bitter or bittersweet and astringent, somewhat foul-smelling when fallen and decomposing; seeds usually 5, 1 in each cell of the ribbed, bony endocarp unit. Weedy in thickets, floodplains, neighborhoods, woods, etc. Native from Asia to Australia, originally cultivated for ornament and definitely established in our area. E. 1/2 TX; escaped from cultivation as far N. as SE. VA. Flowering Mar.-May; fruiting in the fall. Fall color bright clear yellow.

Although the wood has been used for firewood, tool handles, furniture, cigar boxes, etc. (Mabberley 1987), the tree tends to be brittle and readily drops branches in storms. The limbs, the fruits, and the large leaf rachises make litter when they fall, so the tree is generally regarded as a "trash tree." The ripe fruits are eaten by several species of birds in the spring after they mature; in our area a favorite of the cedar waxwing. Birds that eat the fruit often become intoxicated and fly into windowpanes. The fruit and bark have been used medicinally (Elias 1980), but the fruit are listed as poisonous by Lampe (1985). Human intoxications vary in nature and severity, but fatalities have been recorded.

Herbs, subshrubs, shrubs, and small trees, armed or unarmed. Leaves alternate or opposite, pinnately or palmately compound or simple by reduction, usually thickish, firm, and aromatic, with oil glands at least on the undersides of the leaves (obscure in Ptelea); rachis and/or petiole often winged; stipules none. Inflorescence racemose-cymose, cymose, or an axillary cluster. Flowers perfect or imperfect, plants polygamous, dioecious, or with all perfect flowers. Sepals in ours (4)5, free or fuse, sometimes caducous, rarely none. Petals in ours 3 to 5 (rarely 6 or more), usually imbricate, rarely none. Stamens in ours (1)2(3) times as many as the petals, free or connate, when in two whorls, the outer opposite the petals. Nectary disk present between the stamens and ovary. Gynoecium in ours superior, of (2)4 to 5(many) carpels around a central columella, in ours usually united, but in some only loosely united, rarely carpels only 1. Fruit a capsule, samara, berry, or follicle. Seeds usually with abundant endosperm.

161 genera and 1,700 species worldwide, especially in the tropics; 10 genera and 15 species in TX; 3 genera and 4 species here.

The family is important for citrus fruits from Citrus, Fortunella (kumquat), etc., and for flavorings or herbs such as rue (Ruta). Some are timber trees or have medicinal value. Many taxa are cultivated for ornament, including members of Poncirus, Dictamnus, Skimmia, and so on (Mabberley 1987).

One species native to China; cultivated and sometimes persisting or escaping.

1. P. trifoliata (L.) Raf. Trifoliate Orange, Hardy Orange, Bitter Orange. Shrub or small tree; branches somewhat flattened, green, armed with stout, straight, viciously sharp thorns to 6 cm long. Leaves deciduous, often not present or only sparse even in the growing season, alternate, palmately trifoliolate, leaflets elliptic or obovate, 17 to 40(85) mm long, terminal leaflet tapered to the base and sometimes oblanceolate, lateral leaflets asymmetrical, all entire or with tiny glandular scallops, gland-dotted, midveins and petiole pale beneath; petiole winged. Flowers solitary, perfect, fragrant. Calyx cup-shaped with 3 to 5 sepal teeth; petals 4 or 5 whitish; stamens (8 to 10)15 or more. Fruit globose to subglobose, 3.7 to 5 cm in diameter, yellow or yellowish-orange, with a thick gland-dotted rind, the interior resembling a small orange, often partly hollow, pulp sour, seeds relatively large. Fencerows, old homesites, etc. E. 1/2 TX; cultivated as far north as MA, persisting and escaping in the Mid-Atlantic and southern states. Flowering in spring; fruiting in fall. [Citrus trifoliata L.].

This plant makes a very good barrier hedge with its stout thorns and tolerance of poor soils (Elias 1980). The fruit, though resembling a small orange, is not edible. Lampe (1985) lists it as poisonous, causing gastroenteritis, though serious poisoning cases are unlikely because the fruits are unpleasant to eat.

Deciduous shrub or small tree, unarmed, with pale or whitish bark. Leaves alternate, trifoliolate, glandular. Flowers in terminal cymes or panicles, greenish-white, plants polygamo-dioecious. Sepals 4 or 5(6), quickly deciduous. Petals 4 or 5(6), free, imbricate in bud. Stamens 4 or 5(6), vestigial in pistillate flowers. Disk lobed. Ovary with 2(3) locules, ovules 2 per locule but one aborting. Fruit a flat samara, the wing completely encircling the body.

There are 3 species in N. America; we have the 1 found in TX.

1. P. trifoliata L. Skunk-bush, Skunk-tree, Wafer-ash, Common Hop-tree, Cola de Zorillo. Shrub or small tree 1 to 3 m tall; bark light brown. Leaflets sessile, 2 to 9 cm long. Flowers appearing with the leaves, primarily unisexual by abortion; sepals 1 to 2 mm long; petals usually 4 to 6 mm long, broadly elliptic to ovate or linear-oblong, hirsute within; stamens alternate with the petals; disk forming a gynophore beneath the ovary.

The seeds were formerly used as a hops substitute in beer making, and a tonic made from the plant's juices was considered a quinine substitute (Elias 1980).

There are three intergrading subspecies. Our material belongs to the following subspecies and varieties.

subsp. trifoliata var. mollis T. & G. Woolly Hop-tree. Twigs short-pubescent. Foliage and fruit with glands small, visible only with a lens, mostly less than 0.1 mm across. Leaflets more or less ovate or obovate, lateral leaflets inequilateral at the base, the angle between the lower margin and the midvein ca. 45^o to 55^o, blades herbaceous, sparsely pubescent above, mostly on the veins, lower surface densely short-pubescent, margin crenate-serrate to entire. Samaras ca. 2 cm long, reticulate, mostly 2-carpellate, the body usually less than 1 mm thick and about in the center of the wing or slightly above. Ed. Plat., E., SE., and N. Cen. TX.; in our area usually associated with rock outcrops; NY, Que., and Ont. to NE, S. to FL, AL, and TX. Mar.-May.

subsp. angustifolia (Benth.) V. Bailey var. persicifolia (Greene) V. Bailey. Twigs short-pubescent; glands of twigs, leaves, and fruit large enough to be seen with the naked eye, 0.15 to 0.25(0.3) mm in diameter. Leaflets more or less elliptic, lateral leaflets nearly equilateral at the base, the angle between the lower margin and the midvein usually less than 50^o; blades herbaceous and flexible, thin, shiny and short pubescent along the midrib above, slightly shiny below and thinly pubescent with longer hairs, apices acute to obtuse, bases cuneate, margins serrulate to irregularly serrate or nearly entire. Fruit to ca. 2 cm long, often 3-carpellate, the body often 2 to 3 mm thick, sometimes below the middle of the wing. Rocky stream banks, ravines, pastures, etc. Known from Robertson Co.; Ed. Plat. and N. Cen. TX; TX to OK and AR. Mar.-May.

Shrubs or trees; trunk, branchlets and/or foliage armed with stout prickles; bark aromatic. Leaves alternate, usually deciduous, once odd-pinnately compound, margins of leaflets glandular-crenate or -serrate. Plants polygamous or dioecious; flowers in terminal or axillary clusters, small, yellow-green. Sepals 4 or 5, sometimes more or less united or in some species absent. Petals 4 or 5. Stamens 4 or 5, alternate with the petals, vestigial in female flowers. Carpels 2 to 5, more or less free or slightly united basally, vestigial in male flowers. Each carpel maturing into a one-seeded follicle; seeds shiny and black.

About 250 species of the Americas, Africa, Asia, and Australia; 4 species in TX; 2 known from our area.

Often misspelled "Xanthoxylum". Various species are sources of timber, medicines, or spices (Mabberley 1987).

Biting and chewing a leaf produces a numbing or tingling sensation in the tongue. Plains Indians used the near relative Z. americana in various medicinal preparations (Kindscher 1992); it is possible local tribes used this species in similar ways.

Ours annual or perennial herbs (other taxa also shrubs or trees). Leaves stipulate, opposite (other taxa also alternate or in fascicles), commonly 1 of each pair reduced or sometimes absent, even-pinnately compound or irregularly pinnatifid, leaflets usually in opposite pairs, entire. Flowers perfect, regular or essentially so, ours 4- or 5-merous. Sepals imbricate or valvate in ours, free, persistent or deciduous. Petals usually free, imbricate or convolute in bud. Stamens usually in 2 whorls, free or the outer whorl basally united to the petals. Disk or nectary glands present or absent, sometimes acting as a gynophore. Ovary superior, 2- to 5- or 10-lobed and with as many locules, ovules 1 to many per locule, placentation axile; style 1, often forming a beak on the fruit. Fruit in ours schizocarpic, separating into indehiscent mericarps, often spiny or tuberculate.

27 genera an 250 species of the tropics and subtropics, especially dry areas; 6 genera and 13 species listed for TX by Hatch, et al. (1990); 2 genera and 4 species here.

1. Fruit breaking into 5 spiny, 3- to 5-seeded mericarps; beak of fruit falling with the

Annual or perennial herbs; stems radiating from a taproot, prostrate to ascending, well-branched, with silky appressed hairs and also hirsute, to 3 m long. Leaves opposite, but 1 of each pair smaller or abortive (often alternately so along the stem), even pinnately compound, leaflets 3 to 7 pairs, oblong to ovate or elliptic, base in equilateral. Flowers solitary in the axils of the reduced leaves, 5-merous. Sepals ovate to lanceolate, imbricate, pubescent, deciduous. Petals yellow (or white), obovate, apically lobed or rounded. Stamens 10 in 2 whorls, the outer series opposite and basally adnate to the petals, usually slightly exceeding the inner series; intrastaminal nectary glands present. Ovary ovoid, 5-carpellate and 5-lobed, with 5 locules, densely hirsute-pilose; ovules 3 to 5 per locule. Fruit at maturity a schizocarp separating into 5 indehiscent mericarps, each with 2 to 4 spines dorsally and sometimes small spines and bristly tubercles, the interior divided by oblique cross-septa into 3 to 5, 1-seeded compartments; beak of fruit falling with or before the mericarps.

25 species of the Old World tropics and subtropics; 3 species are weeds introduced into the New World; 2 thought to occur in TX; 1 here.

1. T. terrestris L. Caltrop, Puncture Weed or Vine, Goat-head, Abrojo de Flor Amarilla, Cadillo. Characters of the genus and specifically as follows: Annual; stems to 1.5 m long, hirsute and appressed-sericeous but becoming glabrous. Leaves appressed-silky pubescent, 1 to 4.5 cm long, leaflets 3 to 6 pairs, oblong to ovate, 4 to 11 mm long, 1 to 4 mm wide, inequilateral; stipules lanceolate, 3 to 6 mm long, 0.5 to 1.3 mm broad. Flowers 5 to 10 mm across; pedicels usually shorter than the subtending leaves and pubescent. Sepals ovate, 2 to 3 mm long, 1.5 to 2 mm broad, pubescent; petals 3 to 5(6) mm long, 2 to 3 mm wide; nectary glands free; ovary 1 mm broad. Fruit ca. 1 cm broad (exclusive of the spines), larger spines 4 to 7 mm long. Usually in sandy or gravelly disturbed soils of roadsides, railroad beds, etc. Throughout much of TX except the Gulf Coast and Pineywoods; native to the Mediterranean region and now a widespread warm-temperate weed. Apr.-Nov.

This plant is somewhat poisonous to livestock as it leads to photosensitization (Mabberley 1987).

Annual or perennial herbs. Stems radiating from a central taproot, prostrate to decumbent or ascending, well-branched. Leaves opposite, 1 of each pair often reduced or aborted, commonly alternately so along the stem, even-pinnately compound, leaflets in TX material 3 to 8 pairs, oblong or obovate to elliptic, basally inequilateral and somewhat unequal; stipules membranous, deciduous. Flowers solitary in the axils of the reduced leaves, 5-merous. Sepals lanceolate or subulate to ovate, pubescent, imbricate in bud, persistent or deciduous. Petals orange or yellow (white), obovate, rounded to slightly notched, convolute in bud, macrescent (withering but remaining). Stamens 10 in 2 series, the outer series opposite the petals and adnate to them, usually slightly exceeding the inner series. Ovary ovoid or globose, with 10 lobes and 10 locules, glandular to pubescent. Fruit at maturity schizocarpic, separating into 10 unarmed, indehiscent, 1-seeded mericarps.

17 species of the New World tropics and subtropics; 6 listed for TX (Hatch, et al. 1990); 3 known from our area.

Ours annual or perennial herbs (elsewhere also shrubs and trees), acaulescent or caulescent; usually with sour sap. Leaves alternate or basal, palmately or pinnately compound (rarely unifoliate), with or without stipules. Flowers perfect, regular, 5-merous, often heterostylous, borne in axillary cymose inflorescences or the cymes reduced and flowers umbellate or solitary. Sepals imbricate. Petals sometimes briefly united basally, usually convolute in bud. Stamens 10, more or less in 2 whorls, the outer commonly with shorter filaments, often all basally connate, sometimes only 5 with anthers, anthers attached dorsally. Ovary superior, of 3(5) united carpels, styles usually as many and free, placentation axile, each locule with (1)2 to several ovules. Fruit a loculicidal capsule or berry. Seeds with a basal aril, sometimes explosively propelled from the fruit, endosperm usually abundant and oily.

8 genera and 575 species, primarily of the tropics to a few in temperate regions; 1 genus with 12 species in TX; 6 species here.

The family is important for Averrhoa (Star Fruit) with its edible berry. Oxalis includes weeds, cultivated ornamentals, and some food plants (Mabberley 1987).

Caulescent or acaulescent annual or perennial herbs from rootstocks, bulbs, taproots, rhizomes, and/or stolons. Leaves basal or alternate, simple to palmately or pinnately compound (ours all palmately 3-foliolate), leaflets in ours obcordate to obreniform, entire except for an apical dent or notch, usually folded downward and together at night or in cloudy weather; stipules present or absent. Flowers closing at night and in inclement weather, nodding prior to and after anthesis, dimorphic or trimorphic in length of style and stamens. Sepals persistent. Petals sometimes briefly united basally. Stamens 10, of 2 lengths, basally united. Ovary 5-carpellate, styles 5, free. Capsule more or less cylindric, longitudinally dehiscent. Seeds red to brown, enclosed in a transparent aril that turns inside out to forcibly expel the seed from the capsule.

About 500 species worldwide, especially in S. America and the Cape region of Africa; 12 in TX; 6 here.

Many species, including some of ours, are weedy. Some, such as O. acetosella, have edible foliage, while the tubers of some, such as O. tuberosa of Peru, are root vegetables. Some are cultivated ornamentals. One such is O. tetraphylla. It has 4-foliolate leaves and is often sold as a "shamrock" (Mabberley 1987). Tull (1987) notes that yellow dyes can be made from TX species.

NOTES: It is essential to have a complete specimen for identification. Our purple-flowered species must have the underground portion and the yellow-flowered sorts are best examined for habit and pubescence in the fresh state. Many herbarium sheets cannot be determined with absolute confidence.

Several good references exist (e.g. Lourteig 1979; Eiten 1963), but more work needs to be done to determine the range of the species in Texas. Several species known to occur here were not indicated for our area by Correll and Johnston (1970) or Hatch, et al. (1990).

1. Plants leafy-stemmed; flowers yellow ......................................................................................2

1. Plants acaulescent; flowers purple or pink ..............................................................................4

2(1) Stipules none but petioles jointed just above the base; spreading septate hairs present on stems, petioles, and pedicels; inflorescence often cymose; stems usually erect or

Many older manuals, e.g. Small (1903), used the name O. stricta for plants properly called O. dillenii. Hence, while O. stricta does occur in our area, many uncorrected older collections under that name are actually O. dillenii. It is also possible that once this error in nomenclature was noted and resolved, many sheets were "corrected" to O. dillenii which were, in fact, O. stricta. NOTE: One current trend, as reflected by Kartesz (1998) is to combine O. stricta with the taxon below under O. stricta. This would certainly make identification of most of our yellow-flowered sorrels much easier.

The foliage is edible and can be used in salads. Because the high oxalic acid content can be harmful (especially for those with a tendency toward kidney stones), it should be eaten in moderation (Tull 1987). This plant is an alternate host for rust diseases of maize, sorghum, and Andropogon (GPFA 1986).

Varieties have been described, but the characters that vary do so independently of one another. Plants referred to var. radicans Shinners by Correll and Johnston (1970) are described as rooting at the nodes, which is more typical of O. corniculata. This plant has the same uses and rust diseases as O. stricta, above.

Probable in our area.

= O. debilis Kunth var. corymbosa (DC.) Lourteig) Martius Oxalis. Perennial from a cluster of scaly, fleshy, sometimes whitish bulbs with 3-ribbed scales; fibrous roots present as well; stem none, plants to ca. 30 cm tall. Petioles slender, more or less villous; leaflets 2.5 to 5 cm broad, obcordate, apical notch narrow and often deep, usually with small reddish-brown callosities near the margin, with scattered hairs above, paler and more densely pubescent beneath. Scapes villous, commonly exceeding the foliage, cymes often compound (occasionally umbellate), usually with several to many flowers; pedicels 1 to 3 cm long, sparsely appressed-pubescent. Sepals elliptic or oblong to linear, 4.5 to 6 mm long, glabrous or essentially so, the apex of each with 2 confluent orange callosities or tubercles; petals violet to rose-purple, 12 to 15 mm long; shorter filaments usually glabrous and the longer pubescent; styles usually pubescent. Cultivated ground, waste places, and fields. SE. TX; in our area known from at least Brazos Co.; native to tropical Amer.; introduced in the U.S. from FL to TX, N. to SC. Mar.-June. [Ionoxalis martiana (Zucc.) Small; O. martiana Zucc.; treated as O. debilis Kunth var. corymbosa (DC.) Lourteig by Kartesz (1998)].

Ours annual, biennial, or perennial herbs (elsewhere also shrubs). Leaves basal or alternate, usually lobed or divided to compound, stipulate. Flowers perfect, regular or essentially so, ours 5-merous, solitary or in cymose inflorescences. Sepals imbricate in bud, persistent. Nectary "disk" of 5 glands alternate with the petals. Stamens as many as to twice as many as the sepals, but some or all of the outer series staminodial, if only as many as the sepals then opposite them. Ovary superior, in ours 5-carpellate and 5-locular, ovules usually 2 per locule, but only one maturing; carpels developing long stylar beaks, these united into a column. Fruit at maturity dry, the carpels with their beaks separating basally from the central fruit axis, often elastically so; seeds with little or no endosperm.

14 genera and 730 species, primarily in the temperate zones; a few are tropical; 2 genera and 9 species in TX; 2 genera and 4 species here.

The family is important for cultivated ornamentals in Geranium and Pelargonium (garden Geraniums). Since many members have aromatic essential oils, some have uses in medicines or perfumes (Mabberley 1987).

Annual, biennial, or perennial herbs, our species with at least a short stem. Leaves of ours palmately lobed, cleft, or divided. Flowers on axillary peduncles, pedicellate in pairs subtended by bracts, regular to slightly irregular. Petals in ours white to pink or marked with darker purple. Stamens 10, usually all fertile (rarely only 5), the 5 longer ones alternate with the petals and with glands at the base. Each style portion glabrous to soft-pubescent on the inner surface, remaining attached apically to the central column, the lower portion and the carpel curling upwards at maturity. Seeds minutely pitted.

About 300 species of temperate regions and the montane tropics; 6 in TX; 2 here.

Many species are cultivated for ornament, especially as ground covers, with flowers ranging from white to blue, pink, red, and magenta. However, the common window-box type geraniums belong to the genus Pelargonium (Mabberley 1987).

Annual, winter annual, or perennial herbs, usually forming a rosette and with spreading to ascending branches. Leaves petiolate, entire and palmately lobed but pinnately veined, pinnately lobed, pinnate-pinnatifid, or pinnately compound. Inflorescence umbellate, the peduncles axillary; flowers 5-merous. Upper 2 sepals sometimes smaller than the lower 3. Stamens 10 in 2 series, the outer 5 sterile or reduced, the inner fertile and opposite the sepals. Mature carpels fusiform, ultimately dehiscent and the style portion elastically separating basally from the central axis and twisting when dry, bearded on the inner surface; seed surface smooth. As the fallen mericarp with the attached style portion dries, the style untwists, "screwing" the fruit into the soil.

About 60 species widespread in temperate and subtropical regions; 3 species in TX; 2 known from our area.

1. Leaf blades simple, shallowly to deeply palmately or pinnately lobed but the veins pinnate ..

This plant provides some forage for livestock. The root has been used as a dye source (Mabberley 1987).

Trees, shrubs, woody vines, or rarely herbs, sometimes armed. Leaves alternate (rarely opposite or whorled), usually pinnately or palmately compound or lobed, rarely (and not ours) simple; with or without stipules. Inflores-cences terminal, rarely lateral, usually of umbels variously arranged; flowers usually perfect, 4- or 5-merous. Calyx usually represented by small teeth or a truncate cup. Petals usually free, early deciduous. Stamens in ours 5, inserted on a nectary disk. Ovary in ours inferior, with 2 to 5 locules, ovules 1 per locule, styles free or fused. Fruit a 5-seeded berry (other taxa with drupes or rarely schizocarps).

57 genera and 1,800 species, primarily of the tropics, especially Indomalaysia and the Americas, a few temperate; 1 genus with 2 species in TX; 1 species here.

The family is very closely allied to the Apiaceae and is included within in by some taxonomists, including Thorne (see Zomlefer 1994).

Ornamental genera include Aralia, Hedera (e.g., English Ivy), Schefflera, Polyscias, Fatsia, etc. Some taxa have medicinal value, notably Panax (Ginseng) (Mabberley 1987).

Perennial herbs, shrubs, or small trees, often with aromatic or spicy-scented roots. Leaves alternate (sometimes solitary), compound or multiply compound, leaflets toothed. Flowers in umbels grouped into terminal panicles, small, 5-merous. Ovary 5-celled, styles 5, free or fused basally, stigma capitate. Fruit a 5-seeded berry topped with the persistent style; seeds flattened.

About 36 species of N. Amer., E. Asia, and Malaysia; 2 in TX; 1 here.

Some species have ornamental or medicinal value. The young leaves of some (but not ours) are edible. A. racemosa (Sarsaparilla) provides a traditional flavoring for rootbeer (Mabberley 1987; GPFA 1986).

1. A. spinosa L. Hercules'-club, Devil's-walking-stick, Angelica Tree. Shrub or small tree, fast growing and short-lived, to 12 m or more tall, ultimately developing a stout trunk to 30 cm in diameter; branchlets and leaves prickly. Leaves bipinnately compound, to 1 m long or more, primary leaflets usually with 5 or 6 pairs of secondary leaflets, secondary leaflets ovate to broadly elliptic, 5 to 10 cm long, to 6 cm broad, basally rounded to cuneate, apically acuminate or acute, margin serrate or serrulate, paler below, midvein and/or rachis and rachillas with prickles. Flowers small, whitish, in umbels arranged in a large compound panicle; peduncles and pedicels pilose. Fruit a black berry to ca. 6 mm in diameter, topped with the style, juicy. Woods, usually along streams; rare in our area but known from Brazos and Madison Cos.; FL to TN, N. to NJ, PA, OH, IL, MO, and OK. Flowering May-June.

The fruit is eaten by small mammals and birds. The bark, roots, and berries have been used medicinally, usually in stimulants (Elias 1980). Tull (1987) says the fruit can be toxic if eaten raw in large amounts, but the plant is not listed by Lampe (1985) as poisonous.

A large family with 410 genera and ca. 3,100 species worldwide, especially abundant in the N. temperate and tropical montane zones; 44 genera and 78 species reported for TX; 24 genera and 40 here. The work of Mathias and Constanct (1951) is an old but invaluable reference for complete descriptions, county-level distribution information, and exceptional illustrations.

The Apiaceae is closely allied with the Araliaceae and the two families combined in some treatments--for a concise discussion see Zomlefer (1994). This family has traditionally been included within the Rosidae (e.g., Cronquist 1981), but recent evidence suggests that it should be included within a more broadly-defined Asteridae (see e.g., Plunkett, et al. 1996).

The family is important for several vegetable crops, including carrot (Daucus), celery (Apium), and parsnip (Pastinaca). In addition, the family is the source of many herbs (of leafy origin) and spices (dried fruits) including dill (Anethum), caraway (Carum), cilantro and coriander (Coriandrum), cumin (Cuminum), fennel (Foeniculum), parsley (Petroselinum), and anise (Pimpinella), etc. (Mabberley 1987). Some taxa are deadly poisonous, such as Cicuta and Conium. The toxins are usually 17-carbon polyacetylenes, though the element in Conium is an alkaloid (Cronquist 1981; Lampe 1985). Other genera can cause phytophotodermatitis, that is, contact sensitizes skin to ultraviolet light, resulting in sunburn-like effects (Lampe 1985).

NOTES: Particular characters of the mature fruit are most diagnostic of genus, but making cross-sections and examining them under a compound microscope is not always practical or possible. The following key is based largely on vegetative, inflorescence, and external fruit characters which are more readily available. However, a complete specimen, including roots and mature fruit, is still necessary.

Escapes of cultivated taxa such as dill, coriander, and fennel are almost unknown in our area. These taxa are not included but, if found, may often be identified by their characteristic fragrances. However, because of the similarity of poisonous species to harmless ones, it is strongly recommended that one NEVER eat wild umbels.

1. Leaves essentially simple (or if lobed, the sinuses narrow, the lobes more or less touching, and the blades reniform-orbicular) ..........................................................................................2

1. Leaves--at least some of them--compound, dissected, or deeply lobed with broader sinuses between the lobes .......................................................................................................5

2(1) Leaves reniform-orbicular or cordate ......................................................................................3

2. Leaves not reniform orbicular or cordate, usually proportionately longer ..............................4

3(2) Involucre of 2 conspicuous bracts; secondary ribs present on fruits; petioles sheathing ........

Twenty species, mostly of the Southern Hemisphere, primarily in S. Afr; we have the one species that is a pantropical weed.

1. C. asiatica (L.) Urban Spadeleaf. Perennial from slender horizontal rootstocks, bearing plantlets or leaves at each node; stems 1 to several dm long, rooting at the nodes; herbage glabrous to tomentose. Leaves of each plantlet all essentially basal, blades ovate-cordate to oblong, basally cordate to truncate, apically rounded, 1 to 5 cm long, palmately veined, margin weakly sinuate, denticulate, shallowly repand, or entire; petiole often with a tuft of hairs at the apex, to 30(35) cm long, usually shorter, often reddish, base sheathing. Flowers in 1 to 5, loose to capitate simple umbels per plant, each with 1 to 4 flowers; peduncles axillary, varying in length but usually shorter than the subtending leaves, to ca. 12 cm long; involucre of 2 oblanceolate, scarious bracts; pedicels to 4 mm long. Calyx obsolete; petals white to rosy or greenish, spreading, triangular, commonly pubescent abaxially; anthers purple; stylopodium obsolete; styles shorter than the petals, spreading-reflexed. Fruit transverse-ellipsoid, constricted at the commissure, strongly flattened laterally, 3 to 4 mm long, 3 to 5 mm broad, glabrous, more or less strongly reticulate- veined, the primary ribs filiform and evident, secondary ribs evident, seed face flat, an oil-bearing layer present beneath the epidermis, this sometimes with small oil tubes, a thickened layer of cells usually surrounding the seed cavity. Marshes, bogs, stream edges, and other wet places. E. 1/2 of TX; DE to FL along the coastal plain, W. to TX; pantropical and also W. I., Mex., Cen. and S. Amer., and Asia. May-Sept; to Oct. in fruit. [Includes var. floridana Coult. & Rose; C. erecta (L.f.) Fern; C. repanda (Pers.) Small; Hydrocotyle erecta L.f.]

According to Mabberley (1987), this plant is sometimes grown as a cover crop and also has edible leaves.

Low perennial herbs from creeping rootstocks, most with arching or horizontal stems and rooting at the nodes, occasionally in floating mats. Herbage glabrous to pubescent. Leaves 1 per node, peltate and more or less orbicular or else cordate-reniform with the petiole attached at a sinus; margin entire to crenate or lobed; petiole relatively slender, base not sheathing. Inflorescence a simple or compound umbel, or with an umbel-like cluster of flowers at the base and the secondary rays bearing umbels or spikes (thus a proliferous umbel), or with flowers in interrupted spikes or verticils; peduncles shorter than to longer than the leaves; involucre of several to many inconspicuous bracts. Flowers small, white to green or yellow. Calyx teeth minute or obsolete. Petals ovate. Stylopodium conical to depressed. Fruit more or less laterally compressed, ovoid to elliptic, wider than long, dorsal surface acute or rounded, dorsal and lateral ribs present or absent, seed cavity usually with surrounding strengthening cells, seed face flat to concave.

About 75 to 100 species worldwide, especially in the tropical and S. temperate zones; 4 species in TX; 3 here.

Two varieties in Texas, both of which are found here, and one of which may prove to be a distinct species.

var. verticillata Whorled Water-pennywort. Leaf blades with 7 to 14 veins and 8 to 13 shallow lobes, petioles to 26 cm long. Inflorescence an axillary, interrupted spike, usually once bifid (rarely twice to four times bifid), to ca. 17 cm long, verticils up to 6 cm apart, each with 2 to 7 flowers; flowers and fruit subsessile. Jun.-Aug.

Not to be confused with H. bonariensis Lam., a plant of the southern and coastal plains, which has proliferous umbels (base of each inflorescence a floriferous umbel and each secondary ray bearing an umbel or spike.).

var. triradiata (A. Rich.) Fern. Leaf blades with 8 to 14 veins and 8 to 14 shallow lobes, petioles to 35 cm long. Inflorescence an axillary simple (rarely branched) spike to 22 cm long, the verticils few and up to 4 cm apart, each with 4 to 15 flowers; pedicels to 1 cm long. May-Aug. Treated by Kartesz (1998) as Hydrocotyle prolifera Kellogg. [H. canbyi Coult. & Rose; H. australis Coult. & Rose].

Annual, biennial, or perennial herbs from rootstocks or taproots, caulescent and erect to prostrate or acaulescent. Herbage usually glabrous. Leaves thin-textured to coriaceous, entire to palmately or pinnately lobed or divided, venation pinnate or parallel, margins often spinose or ciliate; petioles sheathing, sometimes septate. Inflorescences capitate, solitary or in racemes or cymes; involucre of 1 or more whorls of entire, lobed, or dissected bracts; florets white to purple or blue, sessile, each subtended by an entire to lobed bractlet; a coma or tuft of bractlets sometimes crowning the head. Calyx teeth ovate to lanceolate, acute to obtuse, persistent in fruit. Stylopodium and carpophore absent. Fruit globose to obovoid, only slightly flattened laterally, commissure broad, surface covered with tubercles or scales, ribs obsolete, oil tubes 5 or obsolete, seed face flat or slightly concave.

About 230 species of tropical and temperate regions (except tropical and S. Africa); 8 in TX; 6 here.

Some species are cultivated for ornament; others are edible or used regionally in herbal medicines (Mabberley 1987).

Two varieties in TX; both possible here. The two are sometimes distinguished only with difficulty and perhaps represent only ecological variants (Mathias and Constance 1951). Some treatments combine the two (e.g., Godfrey and Wooten 1981; GPFA 1986).

var. yuccifolium Rattlesnake Master, Button Snakeroot. Plants 3 to 8 dm tall from fascicled tuberous roots. Basal leaves stiff, broadly linear, to 1 m long and 1 to 3 cm broad, acute, cauline leaves linear, marginal bristles usually solitary, rarely grouped. Heads 1 to 2.5 cm in diameter; involucral bracts 6 to 10, ovate-lanceolate, to 15 mm long, cuspidate, mostly entire; bractlets similar to the bracts, entire to minutely serrulate, longer than the fruit. Sepals ovate, obtuse, minutely mucronate. Open prairies and woods. Blackland and Coastal Prairies and the Timber Belt; CT to FL, W. to MN, KS, and TX. May-Aug.

By far the more common variety in our area. Native American tribes used the leaves and fruit in ritual and the roots in medicines to treat snakebite and bladder trouble (Kindscher 1992).

var. synchaetum Gray ex Coult. & Rose Plants smaller than the typical variety, slender. Basal leaves 15 to 35 cm long, 5 to 10 mm broad, marginal setae 3 to 10 mm long, in groups of 2 to 4. Heads subglobose, 10 to 15 mm broad; involucral bracts 6 to 9, linear-lanceolate, 5 to 10(25?) mm long, entire or with a few teeth; bractlets similar to bracts but wider, ca. 5 mm long, longer than the fruit. Sepals acute. Pine woodlands; possible in E. Grimes, Leon, and Madison Cos.; Timber Belt and Coastal and Blackland Prairies; GA and FL, W. to TX and OK. May-Jun. [E. synchaetum (Coult. & Rose) Coult. & Rose].

Annual, perennial, or rarely biennial herbs from woody or fibrous taproots (elsewhere also shrubs), caulescent (as ours) or rarely acaulescent, low to erect or spreading, branches dichotomous or alternate. Herbage glabrous and often glaucous. Basal leaves usually entire and parallel-veined, with sheathing petioles, stem leaves usually sessile and clasping, auriculate, or perfoliate. Flowers in axillary and terminal compound umbels; involucre absent or of conspicuous foliaceous bracts; primary rays spreading to ascending; involucel of broad foliaceous bracts, often connate and occasionally colored, in some species much exceeding the flowers and fruit; pedicels spreading. Calyx obsolete. Petals with an inflexed tip, yellow, greenish, or tinged with purple. Stylopodium depressed-conic; carpophore completely bifid. Fruit oblong to orbicular or ellipsoid, slightly flattened laterally, constricted at the commissure, glabrous to tuberculate, ribs filiform, oil tubes many and distributed around the mericarp or several in the spaces between the ribs and on the commissure, OR oil tubes absent, seed face plane.

About 70 species, mostly circumboreal, also represented in Africa; 2 species introduced in TX; 1 known from our area.

1. B. rotundifolium L. Roundleaf Throughwax. Annual from a slender taproot; stem usually simple below, 2 to 6 dm tall, erect or the branches spreading; herbage glabrous and often glaucous. Basal and lower leaves oblong to obovate-lanceolate, to 8 cm long and 5 cm broad, apically rounded, base subpetiolate or nearly perfoliate, upper cauline leaves (long-)ovate, perfoliate, apically rounded, all major veins arising from the point of attachment. Peduncles 2 to 7 cm long; involucre lacking; primary rays 4 to 10, 5 to 15 mm long, spreading-ascending; involucel of 5 or 6 broadly ovate to obovate, short-acuminate bracts 8 to 12 mm long, 6 to 10 mm broad, basally united, much exceeding the flowers and fruits; pedicels 10 to 12 per umbellet, equalling or shorter than the mature fruits. Flowers yellow, petals 0.5 to 0.8 mm long. Fruit oblong to ovoid, 2.5 to 3 mm long, 1.5 to 2 mm broad, dark purple-brown, smooth, ribs filiform, seed face slightly concave. Southern Blackland Prairies; native to the Medit. region; widely and sporadically introduced in E. and Cen. U.S. Rare or absent in our area in recent years, but known from at least Brazos and Washington Cos. Mar.-Jun.

A monotypic genus.

1. C. digitatum DC. Finger Dog-shade. Glabrous annual herb (1.5)3 to 5 dm tall from a fascicle of fibrous roots; stem erect, slender, few-branched below, dichotomously branched in the inflorescence region. Basal leaves simple, to 12 cm long and 5 cm broad, blades linear-lanceolate, tapered to a sheathing petiole-like base, acute at apex, entire, with cross-septa, major veins parallel, cauline leaves palmately 3- to 5-parted, the divisions linear-lanceolate to linear, 3.5 to 12 cm long, 1 to 6 mm broad, acute, tapered to the base, entire, some with visible septa. Inflorescences axillary and terminal compound umbels; peduncles 1.5 to 1.8 cm long; involucre of a few unequal linear bracts to ca. 1.5 cm long or else absent; primary rays 2 to 10, 1 to 4 cm long, unequal, slender, sometimes a few flowers present among the rays, representing a sessile umbellet; involucels usually absent or of a few linear bracts shorter than the pedicels; pedicels 2 to 11 per umbellet, 5 to 20 mm long, spreading-ascending. Flowers 2.5 to 3 mm broad; calyx teeth prominent, ovate; petals white, tips narrowed and inflexed; styles short, divergent, stylopodium conic, carpophore with bifid apex. Fruit ovoid, abruptly tapered to a prominent beak, basally rounded, slightly flattened laterally or nearly terete, dorsal ribs narrow and prominent, lateral ribs with prominent corky wings or bands, but these not protruding beyond the roundness of the fruit, rather making up the roundness of the fruit since the mericarps are flattened, oil tubes dark, solitary in the intervals between the ribs and 2 on the commissure, seed face flat. Wet places--bayous, low woods, ditches, etc. Coastal and Blackland Prairies. S. MO to E. and SE. TX, LA, and MS. May-July.

Fourteen species, primarily of S. Amer.; we have the 1 species found in TX.

1. B. incana Ruíz & Pavòn Hoary Bowlesia, Rabbit Lettuce. Annual from a slender taproot; stems usually several to many from the base, prostrate to suberect, dichotomously branched, 1 to 5(6) dm long or more; herbage densely stellate pubescent to glabrate. Leaves opposite (except the first), petioles slender, lax, to 7 cm long, not sheathing; blades suborbicular to broadly reniform in overall outline, usually broader than long, to 3 cm long and 4.5 cm broad, palmately veined, shallowly to deeply palmately 5- to 7-lobed, lobes entire to dentate; stipules present, lacerate, scarious. Umbels rather inconspicuous, simple, 2- to 6-flowered, usually paired at the nodes; peduncle slender, much shorter than the leaves, to ca. 2 cm long; involucre of a few subulate, lacerate bracts; pedicels 1 to 3 mm long or obsolete, spreading and ascending. Calyx teeth triangular, prominent in flower, ciliate; petals white to purplish, 0.4 to 0.7 mm long; stylopodium depressed-conic, carpophore undivided. Fruit sessile or subsessile, ellipsoid to subglobose, 1 to 1.5 mm long, 2 to 3 mm broad, stellate-pubescent to glabrate, constricted between the mericarps, carpels depressed along the dorsal area, the dorsal region inflated on either side, ribs scarcely obvious. Lawns, vacant lots, low moist woods, etc. Primarily in the SE. 1/2 of TX; FL to CA; Mex. to S. Amer. (Jan.)Feb.-June. [B. septentrionalis Coult. & Rose].

Biennial or perennial herbs from taproots, tubers, rootstocks, or fascicles of woody or wiry fibrous roots, caulescent or acaulescent. Stems slender, low and decumbent or erect and spreading. Herbage glabrous. Leaves subsessile to petiolate, palmately or pinnately divided or ternate-pinnately decompound, the divisions toothed to lobed or entire, rachis sometimes winged, leaves rarely entire; petioles sheathing. Inflorescences terminal or terminal and lateral, irregular, spreading compound umbels; involucre foliaceous, the bracts toothed or lobed; primary rays few, unequal, developed and spreading or else obsolete; involucel of small to large, entire to lobed bractlets; pedicels obsolete to developed and spreading. Flowers white or some shade of yellow, green, or purple, perfect or staminate, the staminate flowers usually more prominently pedicelled. Sepals prominent, free or united, persistent. Petal apices narrowed and inflexed. Stylopodium absent, styles short to elongate, spreading to recurved or coiled. Fruit oblong-ovoid to ellipsoid or subglobose, slightly flattened laterally, the surface densely covered with uncinate bristles (as in ours), tubercles, or scales, ribs obsolete, oil tubes large or small, irregularly arranged with several to many on the dorsal and lateral surfaces and usually 2 on the commissure, seed face flat, concave, or grooved, strengthening cells none.

About 37 species nearly worldwide, except for Australasia; 3 in TX; apparently only 1 here.

Some, but not ours, have medicinal uses.

1. S. canadensis L. Canada Sanicle. Biennial from a short vertical rootstock and woody or wiry fibrous roots, caulescent, 2 to 10 dm tall; stem solitary at the base and alternately or divaricately branched above, 3- to 4-furcate at the top. Basal leaves long-petiolate, blades suborbicular to reniform in outline, 4 to 10 cm long, 2 to 8 cm broad, usually palmately 3-parted, the divisions in turn shallowly to deeply parted (sometimes to near the midrib), margins sharply serrate, stem leaves triangular to suborbicular, 1.5 to 14 cm long, 1.5 to 6 cm broad, palmately 3-parted (or appearing 5-parted by deep division of the lateral lobes), divisions ovate-lanceolate to cuneate-obovate, acute to obtuse, margin serrate and often incised, the teeth minutely spinulose to mucronate; petioles 5 to 20 cm long, reduced upwards and the upper leaves short-petiolate to sessile. Involucre of few (usually 2) ovate-lanceolate, sometimes divided, leaflike bracts 2 to 3 mm long; primary rays few, commonly only 2 or 3, the fertile ones 2 to 30 mm long; involucel of a few very small ovate bracts; umbellets with 4 to 6 flowers of which 2 or 3 are staminate and have pedicels ca. 2 mm long; perfect flowers subsessile. Calyx lobes linear to narrowly lanceolate, acute, longer than the petals, connate below; petals white, staminate flowers sometimes radiate (with larger petals toward the outside of the umbel); anthers white, slightly exserted; styles shorter than the calyx, included and not projecting beyond the bristles in fruit. Fruits usually 3 per umbellet, globose, 2 to 5 mm long, densely covered with yellowish uncinate prickles which are dilated basally and arranged more or less in longitudinal rows, oil tubes solitary in the groove on the dorsal surface and 2 on the commissure, seed face concave. Moist woods, bottomlands, etc., often in shade. Timber Belt and Blackland Prairies; Ont. and VT to MN and SD, S. to FL and TX. Apr.-June. [Sometimes divided into varieties; as described here, includes var. grandis Fern.].

NOTE: S. odorata (Raf.) Pryer & Philiippe (S. gregaria Bickn.) is reported from the Blackland Prairies, but apparently occurs primarily N. and E. of our area. It is similar to S. canadensis but has styles exserted in fruit, greenish-yellow flowers, and calyx lobes shorter than the petals. It may eventually be found in our area.

Annual from a taproot. Stems erect or decumbent, branched. Herbage pubescent to hispid. Leaves 1- to 3-pinnate or pinnately decompound, the ultimate divisions narrow; petioles sheathing. Inflorescences lateral or lateral and terminal, the sessile or pedunculate compound umbels capitate or open; involucre of 1 to few small, narrow bracts or absent; primary rays 6 to 12, either spreading-ascending or else obsolete; involucel of several linear to filiform bracts; pedicels spreading, short to obsolete. Calyx teeth evident to obsolete. Petals white, the tips narrowed and inflexed. Stylopodium thick, conic, carpophore apically bifid or cleft above the middle. Fruit oblong or ovoid, flattened laterally, the surface tuberculate or prickly/bristly, primary ribs filiform, setulose (sometimes hard to see through the bristles), lateral ribs displaced to the commissure; secondary ribs obscured by bristles or tubercles, oil tubes present, solitary beneath the secondary ribs and 2 on the commissure, seed face concave to shallowly grooved, strengthening cells present in primary ribs and absent from the secondary.

About 12 species, mostly of the Mediterranean area; 2 or 3 depending on interpretation; 2 here.

T. arvensis is sometimes meant to include T. japonica (Houtt.) DC. (e.g., GPFA, 1986; Hickman 1993), but Kartesz (1998) maintains T. japonica as a separate species. Where T. japonica is described, it is said to have leaves 1 to 2 pinnately compound and fruit 1.5 to 4 mm long with short, ascending bristles shorter than the width of the fruit--this does not match our material.

Taprooted annuals. Stems slender, erect or spreading, well-branched, sometimes with red or purple tinting. Herbage glabrous. Leaves ternately or ternate-pinnately decompound, ultimate divisions filiform or narrowly linear; petioles sheathing. Inflorescences terminal and axillary compound umbels, peduncles longer than leaves; involucre none; primary rays few to several, erect to spreading, sometimes an umbellet sessile so that flowers are mixed among the primary rays; involucel of a few linear bracts which are shorter than the pedicels; flowers few per umbel, pedicellate, white. Sepals obsolete. Petals obtuse, apices not inflexed. Stylopodium low-conic, styles short, carpophore apically 2-cleft. Fruit ovoid, somewhat flattened laterally and slightly constricted at the commissure, surface with echinate hairs or tuberculate or smooth; ribs filiform, rounded, oil tubes 1 to 3 in the intervals between ribs and 2 on the commissure, seed face grooved.

3 species in the SE. and Cen. U.S., 1 in Arg., and 1 in HI; we have the 3 found in TX.

Taprooted annual or biennial. Stems erect, simple to branched, pubescent. Leaves pinnately decompound, ultimate divisions usually small and narrow. Inflorescences terminal and axillary compound umbels, sometimes compacted by incurving of the rays during fruit development (often opening again when the fruit are mature); involucre of several to many pinnatifid bracts (as in ours), in some taxa the bracts entire or absent; primary rays few to many, unequal, spreading or the outer incurved over the inner; involucre of entire or toothed bracts or absent. Flowers pedicellate, white (often drying yellow), or the central flower of each umbellet rose or purple, rarely all the flowers reddish or yellow, outer petals of each umbellet often radiant. Calyx obsolete (as in ours) or evident, styles short, stylopodium conic, carpophore entire or apically bifid. Fruit oblong to ovate, flattened dorsally, primary ribs filiform, bristly at maturity, secondary ribs winged, each wing with a single row of bristles or prickles, oil tubes solitary under the secondary ribs and 2 on the commissure, seed face slightly concave to nearly flat.

About 22 species nearly worldwide; 2 species naturalized in TX and present in our area.

D. carota is the common edible carrot.

The common garden carrot, colored by carotene, can be treated as subsp. sativus (L.) Schuebler & Martens. The white-rooted and wild plants belong to subsp. carota (Mabberley 1987). While the roots of this plant are edible, but not always palatable--and considering the very real possibility of confusing this plant with the deadly poisonous Conium--it is safest not to sample it. The leaves yield a yellow dye (Tull 1987), but contact with them can cause phytophotodermatitis (Lampe 1985).

A monotypic genus formerly included in Apium. (Sometimes found spelled "Ciclospermum".)

1. C. leptophyllum (Pers.) Sprague Slimlobe Celery, Marsh Parsley. Taprooted annual; stems erect, striate, (2.5)5 to 8 dm tall, alternately-branched above; herbage glabrous. Leaf blades oblong-ovate in outline, to 10 cm long and 8 cm broad, the lower pinnately decompound, upper ternate-pinnately dissected, ultimate divisions narrowly linear to filiform, narrower on the upper leaves; petiole with abruptly expanded sheathing base with a white, hyaline margin, OR uppermost leaves sometimes subsessile. Umbels simple or compound, sessile in the axils or with peduncles to 2 cm long; involucre absent; primary rays 3 to 5, 1 to 2.2 cm long; involucel none; pedicels about 10 per umbellet, unequal, 2 to 8 mm long and ascending or the central flower sometimes sessile; flowers small and white or greenish. Calyx teeth inconspicuous or none; stylopodium short-conic to depressed; carpophore very shortly 2-cleft. Fruit ovoid to suborbicular, 1.2 to 3(4) mm long, 1.5 to 2 mm broad, slightly flattened laterally and constricted at the commissure, glabrous, ribs conspicuous, filiform and rounded, about equal in width, oil tubes dark (giving the mature fruit a decidedly striped appearance), solitary in the intervals between the ribs and 2 on the commissure, seed face plane. Widespread in moist to wet soil, sometimes weedy, in lawns, fields, roadsides, marshes, ditches, borders of ponds, etc. Coastal and Blackland Prairies and Rio Grande Plains; NC to FL, W. to OK and TX; scattered and adventive elsewhere in coastal areas; also W.I. and S. Amer.; a pantropical weed. Feb.-Jun. [Apium leptophyllum (Pers.) F. v. Muell.].

Four species, 3 in the Mediterranean area and the Caucasus; 1 in America.

1. B. americana (DC.) Benth. & Hook. f. ex S. Wats. Prairie Bishop. Taprooted annual; stem erect, slender, branching, 2.5 to 7.5 dm tall, glabrous to somewhat minutely scabrous. Leaf blades ovate-oblong in outline, 2 to 5 cm long, 1 to 3 cm broad, ternate-pinnately decompound, ultimate divisions filiform to very narrowly linear, 1 mm broad or less, obtuse and minutely mucronate, glabrous; petioles 2 to 15 mm long, slightly expanded basally, sheathing. Inflorescences terminal and axillary compound umbels to ca. 5 cm broad; peduncles slightly scaberulous apically; involucre of a few linear, entire to pinnatifid bracts, ultimate divisions linear to filiform; rays 4 to 14, spreading, usually subequal, 15 to 35 mm long, slightly scaberulous apically; involucel bractlets like the involucre, shorter than or equalling the flowers; pedicels 2 to 4 mm long, spreading; flowers white, outer petals often radiant, rather showy en masse. Calyx teeth evident to obsolete; petals with a narrowed, incurved apex; stylopodium low-conic, carpophore divided to the base. Fruit transverse-ellipsoid to subglobose, more or less didymous, flattened laterally, strongly constricted at the commissure, 2 to 3 mm long, 4 to 5 mm broad, glabrous, ribs filiform, curved to follow the contours of the fruit and often appearing as concentric half-circles on either side of the commissure, pericarp hard and very thin, oil tubes none, seed face deeply and broadly concave (as seen in cross-section as the commissural face itself is rounded). Prairies, fields, roadsides, vacant lots, rocky hills, etc. Primarily in N. and Cen. TX in Blackland Prairies and Ed. Plat.; also adjacent OK and AR. Apr.-Jun.

This flower is the last in the temporal sequence: Nothoscordum, Arenaria, Bifora that colors lots and roadsides white in springtime.

Annual herbs from a fascicle of fibrous (sometimes tuberous) roots. Stems erect, slender, sparingly branched. Herbage glabrous. Leaves in ours pinnately decompound, ultimate divisions filiform; petioles sheathing (in some other species leaves reduced to hollow, septate phyllodia). Inflorescences axillary and terminal compound umbels; involucre of entire to pinnate bracts; rays few to many, spreading-ascending to spreading; involucel of entire bractlets; pedicels spreading. Flowers white or rarely pinkish. Calyx teeth small to prominent. Petals with a narrowed, inflexed apex. Styles spreading to reflexed, shorter than to longer than the conic stylopodium; carpophore apically bifid or cleft to the middle. Fruit ovoid to suborbicular, flattened laterally, dorsal ribs filiform, rounded to acute, lateral ribs small or with corky wings, commonly forming a vertical band around the fruit on either side of the commissure, oil tubes solitary in the intervals between ribs and 2 on the commissure, seed face plane.

Six species of SE. and S. Cen. U.S.; 4 in Texas, all present in our region.

These plants can be devilishly hard to separate as each is defined by a set of characters rather than a single feature. Mature fruit is essential for confident identification, and access to positively identified specimens for comparison is of enormous value.

NOTE: For the key below, in counting leaf segments per node on the rachis of the leaves, examine the lowermost nodes of each leaf. Magnification is helpful.

The above description is by Easterly (1957) who listed it as a "proposed species." The original mention was by Coulter and Rose (1900). It is unclear whether this taxon has ever been formally described and provided with a Latin diagnosis. Kartesz (1998) lists it as P. x texense, while Hatch, et al. (1990) listed it as P. texense.

Correll and Johnston (1970) described this plant as having the fruit characters of P. nuttallii and the vegetative characters of P. capillaceum, while Mathias and Constance (1951) referred the taxon to P. costatum, implying similarity there as well. There seems not to have been and further research into this taxon.

The TAMU and TAES collections include specimens which seem to fit the descriptions of this taxon. The plants are tall, often as tall as P. costatum and superficially similar to it. They are often from rounded, swollen bases. The leaves have the bunchy look of P. costatum leaves, but the ultimate divisions are not verticillate, being usually only 3 at each of the lowest nodes of the rachis (as in P. capillaceum). The divisions are elongate-filiform, much longer than those of either P. costatum or P. capillaceum and usually tangled, as in P. nuttallii. The involucral bracts are much longer than those of P. costatum, usually at least some of them 3-cleft as in P. capillaceum, but not as short. The fruits are nearly identical to those of P. nuttallii, with elongate styles strongly recurved in fruit. It is likely that these plants from Robertson, Trinity, and Brazos Cos. (collected Mar.-Oct.) belong to the taxon known as P. x texense--whatever its status. As Easterly (1957) suggested, this group needs more detailed study.

35 species of the N. temperate zone; we have the 1 species found in TX.

This genus does not include the chervil used as a seasoning; that is Anthriscus cereifolium.

1. C. tainturieri Hook. Taprooted annual; stem usually branched near the base, erect to spreading, 1.5 to 9 dm tall, densely retrorsely-hispid to glabrate below, sparsely hispid to hispidulous above. Leaves ternate-pinnately decompound, oblong to ovate in overall outline, 1.5 to 12 cm long, 1.5 to 10 cm broad, ultimate divisions linear to ovate, 1 to 10 mm long, 0.5 to 2 mm broad, more or less running together, obtuse to acute, glabrous to somewhat hispid; petioles sheathing, 3 to 10 cm long, hispid, margin ciliate and somewhat scarious. Peduncles usually obsolete, the compound (or simple) umbels usually borne in the axils of somewhat reduced upper leaves or else terminal; involucre generally none; primary rays 1 to 5, usually about 3, 1.5 to 7.5 cm long; involucel bractlets conspicuous, entire, ovate, rounded to acute, ciliate-margined, usually longer than the pedicels, at least in flower, spreading to reflexed in fruit; pedicels 3 to 20 per umbellet, unequal, spreading, 0.5 to 10 mm long, slenderly clavate. Calyx teeth obsolete; petals white; styles short; carpophore bifid part way to the base. Fruit narrowly oblong, tapered or beaked apically, rounded to tapered basally, 4 to 8 mm long, 1.5 to 2 mm long, slightly flattened laterally, ribs narrower than to wider than the intervals between, oil tube solitary in the intervals and 2 on the commissure, dark, seed face grooved, each rib with strengthening cells.

Two varieties in TX; both found here and often occurring together.

var. tainturieri Ovaries and fruits glabrous. Prairies, vacant lots, roadsides, flowerbeds, woodlands, etc., often on alluvial soil. Widely distributed in TX, primarily in the E 1/2; VA, IN, MO, and KS, S. to FL, TX, and AZ. Mar.-May. [Includes var. floridanum Coult. & Rose; C. floridanum (Coult. & Rose) Bush; C. reflexum Bush; C. texanum Coult. & Rose].

var. dasycarpum Hook. ex S. Wats. Hairyfruit Chervil. Ovaries and fruits noticeably antrorsely pubescent as seen with a handlens. Primarily in the E 1/2 TX; TX E. to AL and N. to MO. Mar.-May. [C. dasycarpum (Hook ex S. Wats.) Nutt. ex Small; C. procumbens (L.) Crantz var. dasycarpum (S. Wats.) Coult. & Rose].

A monotypic genus of the SE. U.S.

1. T. aethusae Nutt. ex DC. Taprooted annual; stem erect, 2 to 5.5 dm tall, simple below, usually branched above, glabrous and somewhat striate. Leaves pinnately decompound, 8 to 10 cm long, ultimate divisions linear, 2 to 12 mm long, 0.5 to 1.5 mm broad, acute to acuminate, leaves little if at all reduced upwards; petioles 5 to 20 mm long, sheathing. Inflorescences terminal and axillary compound umbels; peduncles 4 to 9.5 cm long; involucre of 1 to several linear (or leaflike) bracts 3 to 15 mm long, usually entire, rarely divided; primary rays 2 to 4, 5 to 15 mm long, unequal to subequal; involucel bractlets like the involucre, 3 to 8 mm long; pedicels 2 to 8 per umbellet, 1 mm or less long, the flowers and fruits thus subsessile. Calyx teeth prominent, to 1 mm long, linear or narrowly triangular, unequal, persistent but fragile; petals white, apically narrowed and inflexed, stylopodium conic, carpophore completely bifid. Fruit oblong-linear, 8 to 10 mm long, truncate to rounded basally, apically blunt except for the stylopodium, slightly flattened laterally, glabrous, primary ribs obsolete but secondary ribs and commissural face corky and obvious, oil tubes small, solitary under the secondary ribs and 2 on the commissure, essentially embedded in the seed and adherent to it, seed face flat to slightly concave. Common in river bottoms and terraces, in moist woods, and sometimes along roadsides. Blackland Prairies, Coastal Prairie, and Timber Belt; TX N. to AR, E. to AL. Apr.-June; collected in fruit as late as July.

Two (perhaps 3) species of temperate regions; 1 naturalized in S. Afr.; 1 species introduced circumboreally; we have the 1 species naturalized in TX.

Species of Conium are fatally poisonous if eaten. This is the only member of the Apiaceae whose toxins are alkaloids (Lampe 1985; Mabberley 1987).

1. C. maculatum L. Poison Hemlock. Biennial herb from a stout white taproot; stem erect, glabrous and often glaucous, 0.5 to 3 m tall, branched, usually spotted or mottled with purple; fresh foliage sometimes also purple-spotted, said to have an unpleasant "mousy" odor when crushed (Lampe 1985). Leaves pinnately decompound, blades broadly ovate in outline, 1.5 to 3 dm long, 5 to 30 cm wide, ultimate divisions bluntly lance-oblong, pinnately incised; petioles as long as to longer than the blades, sheathing, bases expanded and hyaline. Inflorescence a compound cyme of axillary and terminal compound umbels; involucral bracts short, ovate-acuminate, hyaline-margined, much shorter than the rays, reflexed at anthesis; primary rays usually many, 15 to 25 mm long, spreading-ascending, subequal; involucel bractlets similar to involucre but smaller, shorter than the pedicels, and with narrow but visible midribs; pedicels ca. 15 per umbellet, 4 to 6 mm long in fruit, ascending; flowers 2 to 3 mm across. Calyx teeth obsolete; petals white, broadly obovate, with narrow, inflexed apices; styles reflexed, stylopodium depressed-conic, carpophore undivided. Fruit broadly ovoid to subglobose, flattened laterally, 2 to 2.5 mm long, ca. 2 mm broad, glabrous, in mature dry fruit the ribs prominent, obtuse, undulate and crenate, oil tubes many, very small and irregular, seed face narrowly and deeply grooved. Waste places, fencerows, stream banks, low areas, thickets, etc., usually in moist soil in the S. 1/2 TX; native to Eurasia and widely introduced in N. and temperate regions of the W. Hemis. (except Alaska). Not very common in our area and seldom collected in recent years, but definitely known and to be expected. May-Aug.

Fatally poisonous to humans and livestock. According to tradition, this is the plant used to kill the philosopher Socrates. All parts of the plant contain the poisonous alkaloids, especially the root and fruits. Symptoms of Conium poisoning are similar to those of nicotine poisoning; severe intoxications result in death due to respiratory failure (Lampe 1985). This plant was formerly used in medicinal preparations (Mabberley, 1987)--one hopes in small doses and with great judiciousness. The similarity of this plant to white-rooted "wild carrots" (Daucus carota) has been the cause of many an unfortunate accident and is a strong argument against eating any wild umbellifer.

About 25 species from W. N. Amer. to Cen. Am. (possibly northern S. Amer.); we have the 1 species found in TX.

1. T. texana Gray (or A. Gray) Texas Tauschia. Acaulescent perennial herb from a taproot; stems 1 to 4 dm tall, decumbent to erect, entirely glabrous. Leaves pinnately compound, blades oblong, 10 to 15 cm long, 2 to 4 cm broad, leaflets ovate in outline, petiolulate, 7 to 15 mm long, 5 mm broad, the larger pinnately lobed or parted, ultimate divisions cuneate, obtuse, minutely apiculate, the whole leaf repeatedly divided so it is not immediately obvious what is a leaf and what is a leaflet; petioles slender, sheathing, 5 to 10 cm long. Inflorescences compound umbels; peduncles scapose, arising directly from the base of the plant, 1 to 4 dm long; involucre absent or of 1 foliaceous bract; primary rays bearing fertile flowers 5 to 8, 5 to 25 mm long, unequal, shorter rays bearing reduced flowers also present; involucel of several linear-lanceolate, connate bractlets about as long as the flowers at anthesis, shorter than the fruit; pedicels in fertile umbels few to several, 1 to 2 mm long. Calyx teeth minute; petals yellow, with narrowed, inflexed apices; styles slender, spreading, stylopodium evidently lacking or represented by a low bump, carpophore bifid to about the middle. Fruit ovoid in outline, flattened laterally, 3 to 4 mm long, 2 to 3 mm broad, ribs filiform, not especially prominent, oil tubes 3 or 4 in the intervals between ribs and 4 on the commissure, seed face deeply sulcate (as seen in fruit cross-section; commissural face is convex). Wet woods, alluvial thickets, etc. of the S. part of the Blackland Prairies and coastal regions; infrequently collected in our area but known at least from Grimes Co.; endemic. Feb.-June. [Museniopsis texana (Gray) Coult. & Rose].

Taprooted annuals, plants usually low, erect or diffuse, well-branched. Herbage often roughened. Leaves ternately or ternate-pinnately decompound, ultimate divisions linear to spatulate; petioles sheathing. Inflorescences pedunculate or sessile axillary or terminal compound umbels; involucre usually none; primary rays few, ascending or spreading-ascending, unequal; involucel of several slender, entire to toothed bractlets; flowers few per umbellet, sessile or with slender, unequal pedicels. Calyx teeth obsolete. Petals white, apices obtuse and not inflexed. Styles short, stylopodium low-conic; carpophore apically 2-cleft. Fruit ovoid-oblong to ovoid, laterally compressed, ribs prominent, rounded or acute, roughly scabrous to glabrous, lateral ribs with or without callous teeth or corky appendages, contiguous and forming a vertical, often corky band around the commissure, oil tubes 1 to 3 in the intervals between ribs and 2 to 4 on the commissure, pericarp made almost entirely of strengthening cells, seed face flat to concave.

3 species of the S. Cen. and SW. U.S.; 2 in TX; 1 known locally.

1. A. butleri (Engelm. ex S. Wats.) Coult. & Rose Butler's Sand-parsley. Plants low, 4 to 5(12) cm tall, branched from the base. Leaf blades oblong, to 2.5 cm long, to 15 mm broad, biternately or ternate-pinnately compound, ultimate divisions linear, obtuse, minutely mucronate, 1 to 8 mm long, 1 to 2 mm broad, glabrous; petioles 5 to 30 mm long, basally sheathing on the lower leaves, entirely sheathing on the upper leaves. Umbels sessile in the leaf axils, irregularly compound; involucre absent; primary rays 2 to 6, unequal, to 20 mm long or obsolete; involucel of few to several foliaceous bractlets shorter than the pedicels; pedicels 1 to 10, unequal, 1 to 6 mm long. Fruit ovoid, 2.5 to 3 mm long, 1 to 1.5 mm broad, glabrous to sparsely rough with tiny teeth; ribs prominent, subacute, oil tubes single in the intervals and 2 on the commissure, seed face flat or nearly so. Mostly in low woods, floodplains, bottomlands, etc.; Blackland and Coastal Prairies and Timber Belt; easily overlooked and not much collected; also AR, OK, and sporadically weedy elsewhere. Mar.-Apr.

Herbs from fascicles of tuberous roots. Stems erect. Herbage glabrous. Leaves once odd-pinnately compound (as in ours), ternately compound, or reduced to hollow, septate phyllodia; leaflets (if present) linear to very much broader, entire to serrate or incised, usually sessile and distinct, quite discernable as leaflets; petioles sheathing. Inflorescences terminal and axillary, pedunculate compound umbels; involucre of a few narrow bracts or absent; primary rays few to many, usually spreading-ascending; involucel similar to the involucre or none; pedicels ascending to spreading. Calyx teeth minute or prominent. Petals white to purple or maroon, with narrowed, inflexed apices. Styles slender, spreading, stylopodium conic; carpophore completely bifid. Fruit strongly compressed dorsiventrally (parallel to the commissure), oblong-obovoid, glabrous, dorsal ribs (on the flat "faces") filiform, lateral ribs (at the edges of the fruit) at maturity with broad thin wings and basal nerves so that the fruit faces appear 5-nerved, oil tubes large, single in the intervals between ribs and 2 to 6 on the commissure, seed face flat, strengthening cells present under the dorsal ribs and nerves of the lateral ribs.

7 species of N. Amer., 1 species extending to Cuba; 2 in TX; 1 in our area.

1. O. rigidior (L.) Raf. Cowbane, Water-dropwort. Plants from slender tuberous roots; stems 6 to 15 dm tall, slender to rather coarse, somewhat striate. Leaves oval to triangular or lanceolate in outline, blades 10 to 30 cm long, 10 to 25 cm broad, once odd-pinnately compound, leaflets 5 to 11, sessile, quite variable in shape, linear to lanceolate, 7 to 15 cm long, 5 to 45 mm broad, entire to irregularly and remotely toothed to rather regularly and saliently toothed, rarely 3-lobed apically; petioles 5 to 10 cm long. Inflorescences to 15 cm broad in fruit (smaller in flower); peduncles 6 to 30 cm long; involucre of a few linear, attenuate, entire bracts 1 to 2 cm long; primary rays 15 to 45, spreading, 3 to 12 cm long, subequal; involucel of a few linear-filiform bractlets 3 to 5 mm long; pedicels 15 to 45 per umbellet, 5 to 15 mm long, unequal in fruit. Calyx teeth small but conspicuous (with a lens) in flower; petals white, orbicular. Fruit oval to oblong, 4 to 7 mm long, 2.5 to 4 mm broad, ribs and wings as described for the genus but these features obvious only on mature fruit. Bogs, ditches, creekbanks, wet woods, swamps, wet roadsides, etc.; not common but definitely present in our area; Timber Belt and Blackland and Coastal Prairies; NY and NJ to MN, S. to SC, FL panhandle, and TX. Aug.-Oct. [O. turgida Small].

Despite the faintly ominous names, apparently not poisonous--or at least not to humans. (Not listed in the AMA Handbook of Poisonous and Injurious Plants [Lampe 1985]).

Annuals from clusters of fibrous roots, low and diffuse to erect. Stems slender. Leaves entire and septate or once odd-pinnate with elongate leaflets; petioles sheathing. Inflorescence region dichotomously branched, bearing axillary and terminal compound umbels; peduncles well-developed or some inflorescences sessile; involucre of a few, narrow, entire bracts or else absent; primary rays few, spreading-ascending, unequal; involucel of several entire, narrow bractlets shorter than the pedicels; pedicels few per umbellet, spreading. Calyx teeth ovate-lanceolate, visible, not necessarily large, shorter than to longer than the conic stylopodium. Petals white, apices not inflexed. Styles very short, divergent; carpophore briefly bifid apically. Fruit ovoid-oblong to orbicular, basally and apically rounded, slightly compressed dorsiventrally, glabrous, dorsal ribs filiform, lateral ribs expanded and corky, oil tubes single in the intervals between ribs and 2 on the commissure, seed face plane.

2 species of S. and Cen. U.S.; both found here; 1 endemic.

The species can be difficult to determine when the plants are in flower, but mature fruits are characteristic.

1. Fruit ovoid-oblong, 2 to 4 mm long, 1 to 2 mm broad; calyx teeth 0.5 mm long or shorter, shorter than and attached well below the stylopodium; plants typically erect or assurgent ...

Four species of N. Amer., primarily of the E. U.S. and Canada, but present W. to the Pacific NW; we have the 1 species found in TX.

1. Z. aurea (L.) W. D. J. Koch Golden Alexanders, Golden Meadow Parsnip. Perennial from a fascicle of fleshy or tuberous roots (or occasionally one long rootstock); stem erect, usually branched, 3 to 10 dm tall; herbage glabrous. Basal leaves with blades ovate to orbicular in outline, 6 to 10 cm long, to 12 cm broad, biternate or the middle leaflet pinnatifid, leaflets well-defined, ovate-lanceolate, 2 to 5 cm long, 1 to 3 cm broad, acute, margin sharply serrate; petioles 10 to 15 cm long, sheathing, expanded and somewhat hyaline-margined basally; stem leaves similar to the basal, ternate or irregularly compound, the leaflets more lanceolate and sometimes confluent; petioles sometimes reduced upwards. Inflorescences terminal and lateral compound umbels; peduncles 5 to 15 cm long; involucre none; primary rays 10 to 15, spreading-ascending, 1 to 3.5 cm long, unequal; involucel of a few inconspicuous bractlets, 1 to 3 mm long, shorter than or equalling the pedicels, linear, commonly with expanded bases whose white scarious or hyaline margins are ciliate or fimbriate; pedicels several to many, spreading, unequal, 2 to 3 mm long, the central flower of each umbellet sessile. Calyx teeth prominent but not large; petals yellow, apically narrowed and inflexed; stylopodium none, styles in flower equalling or longer than the ovary, slender, spreading, carpophore bifid to about the middle. Fruit oblong-ovoid, 2 to 4 mm long, 1.5 to 2 mm broad, flattened laterally, ribs filiform, oil tubes single in the intervals between the ribs and 2 on the commissure, seed face slightly concave. Mostly in sandy woods and in floodplains; also around ponds, shores, marshes, etc. E. 1/3 TX; ME and Que. W. to Sask., S. to FL and TX. (Mar.)Apr.-Aug.

Herbaceous perennials from stout, sometimes woody fusiform taproots. Stems erect, branched. Herbage puberulent. Leaves bipinnately or ternate-pinnately compound, leaflets crenate to incised or lobed, basally cuneate; petioles sheathing. Inflorescences terminal and axillary compound umbels, exceeding the leaves; involucre none; rays few to many, spreading-ascending, puberulent; involucel of several linear to filiform, entire, puberulent bractlets shorter than the pedicels; pedicels spreading-ascending. Calyx teeth ovate, acute to acuminate. Petals yellow, apically narrowed and inflexed. Stylopodium none; carpophore bifid to the base. Fruit oblong to obovate or orbicular, greatly flattened dorsiventrally (parallel to the commissure), glabrous, dorsal ribs obsolete to filiform, lateral ribs with broad, thin, corky wings, oil tubes indistinct or distinct, 1 to several in the intervals between ribs and 2 to several on the commissure, some also scattered within the pericarp, seed face flat.

2 species of S. Cen. and Cen. U.S.; both represented in our part of the state.

Stands of these plants in flower are quite impressive and possibly worthy of cultivation in the prairie garden or perennial border. The dry infructescences are interesting in arrangements.

NOTE: The two species are, according to monographers of the genus (Mathias and Constance 1951), essentially impossible to tell apart unless mature fruit (with mericarps separating) are present. For determining the proportions of fruit body and wings as mentioned in the key below, it is useful to make a cross-section with a sharp blade and examine it under strong magnification.

1. Lateral wings narrower and thicker than the body of the fruit; oil tubes indistinct, several in the intervals and on the commissure; fruit 5 to 11 mm long, 4 to 7 mm broad .......................

Taprooted annual, biennial, or perennial herb. Stem slender, erect, often branched. Leaves pinnately or ternate-pinnately compound or decompound, ultimate divisions filiform to lanceolate or lance-ovate; petioles sheathing. Inflorescences lateral and terminal compound (rarely simple) umbels, pedunculate or some sessile; involucral bracts many, entire or divided; rays many, spreading-ascending; involucel of many entire bractlets; pedicels spreading. Calyx teeth minute. Petals white, apically narrowed and inflexed. Stylopodium depressed-conic, styles slender, more than twice as long as the stylopodium; carpophore entire or completely divided. Fruit oblong to ovoid, laterally compressed, glabrous, ribs acute, oil tubes single in the intervals and 2 on the commissure, seed face flat.

6 species, primarily of the Mediterranean; also W. Asia and Macronesia; 2 species introduced in TX; 1 here (the other as yet known only from the Trans Pecos).

1. A. majus L. Bishop's-weed, Greater Ammi. Annual; stems usually branched, 2 to 8 dm tall. Basal leaves oblong in outline, 6 to 20 cm long, 5 to 14 cm broad, ternate or once pinnate, leaflets distinct, lanceolate to lance-ovate or oblanceolate, apically obtuse to acute, basally cuneate and somewhat recurved on the rachis, to ca. 4 cm long, 5 to 20 mm broad, margin setulose and serrate, teeth small and even; petioles 3 to 13 cm long, cauline leaves bipinnate, ultimate divisions linear to lanceolate, uppermost leaves much smaller than the lower and with narrower divisions, serrate to slightly laciniate. Inflorescence scabrous; peduncles 8 to 14 cm long; involucral bracts usually longer than the rays, commonly divided, with ultimate divisions linear to filiform; rays to as many as 50 or 60, very slender, 2 to 7 cm long, spreading to ascending in flower, spreading in fruit; involucel bractlets several to many, linear-acuminate, scarious-margined, spreading to reflexed at maturity and slightly longer than the pedicels; pedicels many, unequal, 1 to 10 mm long, spreading-ascending, filiform. Carpophore wholly divided. Fruit oblong, 1.5 to 2 mm long, 1 mm broad or less. Sporadically introduced from Asia in the S. 1/2 TX; widely introduced in the W. Hemis. Mar.-June.

Sometimes cultivated as a cut flower (Mabberley 1987), the seed commonly available.

Perennial from a cluster of fleshy-tuberous or thick fibrous roots, these sometimes hollow-chambered. Stem stout to slender, erect, sometimes the base enlarged and with hollow chambers, sometimes purple-spotted. Leaves 1 to 3 times pinnately compound or ternate-pinnate, leaflet margins serrate and/or incised; petioles sheathing. Inflorescences terminal and lateral compound umbels held above the leaves; involucre inconspicuous, of slender bracts or absent; rays many, slender, spreading-ascending; involucel of several narrow bractlets or none; pedicels spreading, slender. Calyx teeth evident. Petals white or greenish, ovate, apices narrowed and inflexed. Styles short, spreading, stylopodium low-conic or depressed; carpophore completely bifid. Fruit ovoid to orbicular or ellipsoid, laterally compressed, constricted at the commissure or not so, ribs obvious, obtuse and somewhat corky, oil tubes single in the intervals and 2 on the commissure, seed face flat to slightly concave, in one species (not ours) mature fruit rarely seen and plants reproducing by axillary bulbils.

About 7 species of the N. temperate region; 1 in TX and present here. A useful reference is Mulligan (1980).

All parts of these plants, especially the roots, are deadly poisonous to humans and livestock. The toxin, cicutoxin, is a 17-carbon alcohol. Symptoms of ingestion range from nausea to convulsions and death; even non-fatal poisonings can result in post-event chronic effects such as mental deficit (Lampe 1985).

1. C. maculata L. Water-hemlock, Beaver-poison, Musquash Root or M. Poison, Spotted Cowbane. Perennial or biennial, plants stout, from a base of chambered, tuberous or fleshy-tuberous roots, the toxin concentrated in an oily, parsnip-scented, yellow sap contained therein and which turns reddish and then brownish on exposure to air; stems hollow, usually with partitions or chambers below, 0.5 to 2 m tall, glabrous, often glaucous, sometimes purple-spotted below. Leaves 2 to 3 times pinnately compound or ternate-pinnate, to ca. 35 cm long, leaflets varying in shape from narrowly lanceolate to lance-oblong, 2 to 12 cm long, 5 to 40 mm broad, with a few remote teeth to sharply and regularly serrate or incised, enclosures of reticulate veins of lower leaflet surface rounded or squarish (rather than oblong as in other species); petioles of larger leaves 10 to 30 cm long. Peduncles 2 to 10 cm long; involucre of 1 to several slender bracts or sometimes none; rays unequal to subequal, 1.5 to 6(8) cm long; involucel bractlets several, linear to lanceolate, acute to acuminate, scarious-margined, entire to denticulate, 2 to 5 mm long, shorter than to equalling the flowers; pedicels 3 to 15 mm long. Fruit oval to orbicular, 2 to 4.5 mm long, seed face plane to concave. Wet places--swamps, marshes, etc. E., N., and Cen. TX; the species as a whole from AK to SE Mex.

According to Mulligan (1980), four varieties distinguishable mostly on the basis of mature fruit--which are seldom present in herbarium sheets. Two of these varieties are found in TX and are possible here.

var. maculata Leaflets of main stem leaves usually less than 5 times longer than wide; styles longer than 1 mm; mature fruits obviously longer than wide, not constricted at the commissure, dorsal ribs more or less equal in surface display, as wide as or wider than the intervening oil tubes, seed not very oily, not or only slightly grooved under the oil tubes E., Cen., and N. TX; Que. and E. 1/2 U.S., scattered elsewhere. [C. curtissii Coult. & Rose; C. maculata L. var. curtissii (Coult. & Rose) Fernald; C. mexicana Coult. & Rose is considered a synonym, though the description of the fruits of the plants listed as C. mexicana by Correll and Johnston (1970) can be considered to apply to var. bolanderi (below.) May-Sept.

var. bolanderi (S. Wats.) G. A. Mulligan Leaflets of main stem leaves usually less than 5 times longer than wide; styles longer than 1 mm; fruit slightly longer than wide, unevenly and abruptly constricted at the commissure, dorsal corky ribs much smaller than the oil tubes, lateral corky ribs larger than the dorsals and about half the size of the oil tubes, seed very oily, deeply grooved beneath the tubes. E. 2/3 TX, from the Panhandle to the Coastal Plain; NC, IN, MN, and NE, S. to GA, TX, CA, and Mex. Fruits of plants described by Correll and Johnston (1970) under C. mexicana match the description for this variety, though C. mexicana is a synonym for var. maculata (above). [C. bolanderi S. Wats.].

A third variety, var. angustifolia Hook. occurs in the Panhandle of TX. Its cauline leaf leaflets are more than 5 times longer than wide; styles usually less than 1 mm long; fruits not constricted at the commissure. Apparent intergrades between this variety and var. maculata occur in portions of their ranges--more study may be needed.