Agrostis hendersonii Hitchc.

Agrostis hendersonii Hitchc. Jour. Wash. Acad. 20: 381. 1930
Plant apparently annual; culms slender, erect, 2-noded, glabrous, about 11 cm. tall; sheaths glabrous; ligule membranaceous, acute, 2-3 mm. long; blades flat or loosely involute, glabrous, 1-3 cm. long, 1 mm. wide; panicle condensed, about 2.5 cm. long, purplish-tinged; spikelets short-pediceled, 5-6 mm. long; glumes subequal, with a setaceous slightly spreading tip 1-2 mm. long; lemma about 3 mm. long, with 2 setaceous teeth about 0.5 mm. long at the summit, the base or callus pubescent; awn from the middle of the back of the lemma, about 1 cm. long, twice-geniculate, the first bend often somewhat obscure; palea obsolete.
Type locality': Sams Vallev, a few miles from Gold Hill, Jackson Count v, Oregon (Henderson 12387).
Distribution: Wet ground, Oregon and California.

Annuals, Terrestrial, not aquatic, Stems nodes swollen or brittle, Stems erect or ascending, Stems caespitose, tufted, or clustered, Stems terete, round in cross section, or polygonal, Stem internodes hollow, Stems with inflorescence less than 1 m tall, Stems, culms, or scapes exceeding basal leaves, Leaves mostly basal, below middle of stem, Leaves conspicuously 2-ranked, di stichous, Leaves sheathing at base, Leaf sheath mostly open, or loose, Leaf sheath smooth, glabrous, Leaf sheath and blade differentiated, Leaf blades linear, Leaf blades very narrow or filiform, less than 2 mm wide, Leaf blades 2-10 mm wide, Leaf blades mostly flat, Leaf blade margins folded, involute, or conduplicate, Leaf blades mostly glabrous, Ligule present, Ligule an unfringed eciliate membrane, Inflorescence terminal, Inflorescence a contracted panicle, narrowly paniculate, branches appressed or ascending, 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 branches more than 10 to numerous, Lower panicle branches whorled, Flowers bisexual, Spikelets laterally compressed, Spikelet less than 3 mm wide, Spikelets with 1 fertile floret, Spikelets solitary at rachis nodes, Spikelets all alike and fertille, Spikelets bisexual, Spikelet s disarticulating above the glumes, glumes persistent, Spikelets disarticulating beneath or between the florets, Rachilla or pedicel glabrous, Glumes present, empty bracts, Glumes 2 clearly present, Glumes equal or subequal, Glumes equal to or longer than adjacent lemma, Glume equal to or longer than spikelet, Glumes awned, awn 1-5 mm or longer, Glumes 1 nerved, Lemmas thin, chartaceous, hyaline, cartilaginous, or membranous, Lemma 5-7 nerved, Lemma glabrous, Lemma apex truncate, rounded, or obtuse, Lemma distinctly awned, more than 2-3 mm, Lemma with 1 awn, Lemma with 3 awns, Lemma awn less than 1 cm long, Lemma awn subapical or dorsal, Lemma awn once geniculate, bent once, Lemma margins thin, lying flat, Lemma straight, Callus or base of lemma evidently hairy, Callus hairs shorter than lemma, Palea 2 nerved or 2 keeled, Stamens 3, Styles 2-fid, deeply 2-branched, Stigmas 2, Fruit - caryopsis, Caryopsis ellipsoid, longitudinally grooved, hilum long-linear.

Agrostis hendersonii is an uncommon species of grass known by the common name Henderson's bent grass. It is native to northern California and Oregon, where it is a rare member of the flora in scattered vernal pool habitats. It is an annual grass ranging in maximum height from 6 to 70 centimeters. It has short, narrow leaves only a few centimeters long. The inflorescence is a dense, narrow, cylindrical tuft no longer than 5 centimeters in length, made up of small spikelets with hairlike tips and bent awns.

Agrostis hendersonii é uma espécie de gramínea do gênero Agrostis, pertencente à família Poaceae.

Agrostis hendersonii là một loài thực vật có hoa trong họ Hòa thảo. Loài này được Hitchc. mô tả khoa học đầu tiên năm 1930.