Itchgrass

Annuals, Terrestrial, not aquatic, Prop roots present, Stems nodes swollen or brittle, Stems erect or ascending, Stems caespitose, tufted, or clustered, Stems terete, round in cross section, or polygonal, Stems branchi ng above base or distally at nodes, Stem internodes solid or spongy, Stems with inflorescence less than 1 m tall, Stems with inflorescence 1-2 m tall, Stems with inflorescence 2-6 m tall, Stems, culms, or scapes exceeding basal leaves, Leaves mostly cauline, Leaves conspicuously 2-ranked, distichous, Leaves sheathing at base, Leaf sheath mostly open, or loose, Leaf sheath hairy, hispid or prickly, Leaf sheath and blade differentiated, Leaf sheath enlarged, inflated or distended, Leaf blades linear, Leaf blades 1-2 cm wide, Leaf blades 2 or more cm wide, Leaf blades mostly flat, Leaf blades more or less hairy, Leaf blades scabrous, roughened, or wrinkled, Ligule present, Ligule a fringed, ciliate, or lobed membrane, Inflorescence terminal, Inflorescence a dense slender spike-like panicle or raceme, branches contracted, Inflorescence solitary, with 1 spike, fascicle, glomerule, head, or cluster per stem or culm, Inflorescence a panicle with narrowly racemose or spicate branc hes, Inflorescence single raceme, fascicle or spike, Inflorescence with 2-10 branches, Flowers bisexual, Spikelets pedicellate, Spikelets sessile or subsessile, Spikelets dorsally compressed or terete, Spikelet less than 3 mm wide, Spikelets with 2 florets, Spikelets paired at rachis nodes, Spikelets in paired units, 1 sessile, 1 pedicellate, Pedicellate spikelet well developed, staminate, Spikelets bisexual, Spikelets disarticulating above the glumes, glumes persistent, Spikelets disarticulating below the glumes, Spikelets disarticulating beneath or between the florets, Spikelets falling with parts of disarticulating rachis or pedicel, Spikelets closely appressed or embedded in concave portions of axis, Rachilla or pedicel glabrous, Glumes present, empty bracts, Glumes 2 clearly present, Glumes equal or subequal, Glumes equal to or longer than adjacent lemma, Glumes keeled or winged, Glumes 3 nerved, Lemmas thin, chartaceous, hyaline, cartilaginous, or membranous, Lemma 3 nerved, Lemma glabrous, Lemma apex acute or acuminate, Lemma awnless, Lemma margins thin, lying flat, Lemma straight, Palea present, well developed, Palea membranous, hyaline, Palea longer than lemma, Palea 2 nerved or 2 keeled, Stamens 3, Styles 2-fid, deeply 2-branched, Stigmas 2, Fruit - caryopsis.