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