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AGROPYRON Gaertn. Wheatgrass
Plant hermaphroditic, caespitose, annual. Culms erect or ascending or decumbent, glabrous; internodes hollow, terete.
Leaves basal and cauline, not distinctly distichous; sheaths terete, margins open; auricles present; ligules membranous; blades
flat or folded or involute, linear, lax. Spikes bilateral and distichous (about 3 mm or less between spikelets), rachis
persistent, pedicels absent. Spikelets solitary at inflorescence nodes, spreading about 40 ° or more from rachis
, laterally compressed, disarticulation above the glumes, mucronate to short awned, sessile; florets 4-9, reduced floret
at apex, callus glabrous or scabrous, rachilla not extending beyond upper floret; glumes 2, 2-5 veined, opposite
relative to floret position, slightly unequal, not subulate, shorter than first floret, short awned; lemmas
5-veined, chartaceous or coriaceous, glabrous or ciliate, apex entire, mucronate; awns apical (1)
, straight; paleas 2-veined, awnless, glabrous. Stamens 3; anthers yellow. Caryopses aduate to lemma and/or palea,
dorsiventrally compressed. Base chromosome number x=7.
A genus of about six species. These species are from China and Russia. They occur on dry, frequently
stony soils, in full sunlight. Crested wheatgrass (A. cristatum) is an important range revegetation species.
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