Rough Dropseed

Sporobolus clandestinus (Spreng.) Hitchc. Contr. U. S. Nat
Herb. 12: 150. 1908.
Agrostis dandestina Spreng. Mant. Fl. Hal. 32. 1807.
Muhlenbergia dandestina Trin. Gram. Unifl. 190. 1824. (Based on Agrostis dandestina Spreng.)
Vilfa dandestina Nees; Steud. Norn. Bot. ed. 2. 2: 767. 1841. (Based on Agrostis dandestina
Spreng.) ? Vilfa Riehlii Steud. Syn. Oram. 154. 1854. (Type from North America.) Sporobolus canovirens Nash; Britton, Man. 1042. 1901. (Type from St. George, Kansas.)
Perennial; culms relatively stout to slender, erect or spreading, usually cespitose in rather large hunches, glabrous, several-noded, 50-100 cm. tall; sheaths glabrous or the lower pilose, more or less pilose at the throat, except the lower mostly shorter than the internodes ; ligule very short; blades flat becoming involute, tapering to a long fine scabrous point, pilose on the upper surface near base, sometimes also beneath, 1-3 mm. wide; panicles narrow, contracted or spikelike, 5-10 cm. long, terminal and axillary, the terminal often exserted, the axillary usually inclosed in the somewhat inflated sheaths; spikelets 5-7 mm. long, compressed; glumes acute or subacute, glabrous, the first more than half as long as the spikelet, the second longer than the first; lemma sparsely appressed-pubescent, acuminate; palea longer than the lemma, sometimes as much as 10 mm. long.
Type locality: Pennsylvania {Muhlenberg) .
Distribution: Sandy fields, pine harrens, hills, and prairies, Connecticut to Illinois and Kansas, and southward to Florida and Texas.

Perennials, Terrestrial, not aquatic, Rhizomes present, Rhizome short and compact, stems close, Stems nodes swollen or brittle, Stems erect or ascending, Stems geniculate, decumbent, or lax, sometimes rooting at nodes, 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 cauline, Leaves conspicuously 2-ranked, distichous, Leaves sheathing at base, Lea f sheath mostly open, or loose, Leaf sheath smooth, glabrous, Leaf sheath hairy, hispid or prickly, Leaf sheath hairy at summit, throat, or collar, Leaf sheath and blade differentiated, Leaf sheath enlarged, inflated or distended, 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, Leaf blades more or less hairy, Ligule present, Ligule a fringe of hairs, Inflorescence terminal, Inflorescence lateral or axillary, 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 with 2 or more spikes, fascicles, glomerules, heads, or clusters per culm, Inflorescence branches more than 10 to numerous, Flowers bisexual, Spikelets pedicellate, Spikelets laterally compressed, Inflorescence or spikelets partially hidden in leaf sheaths, subtended by spatheole, Spikelet less than 3 mm wide, Spikelets with 1 fertile floret, Spikelets solitary at rachis nodes, Spikelets all alike and fertille, Spikelets bisexual, Spikelets disarticulating above the glumes, glumes persistent, Rachilla or pedicel glabrous, Glumes present, empty bracts, Glumes 2 clearly present, Glumes equal or subequal, Glumes distinctly unequal, Glumes shorter than adjacent lemma, Glumes 1 nerved, Lemmas thin, chartaceous, hyaline, cartilaginous, or membranous, Lemma similar in texture to glumes, Lemma 1 nerved, Lemma body or surface hairy, Lemma apex acute or acuminate, Lemma awnless, Lemma straight, Palea present, well developed, Palea membranous, hyaline, Palea about equal to lemma, Palea longer 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.

Sporobolus clandestinus, common names rough dropseed and rough rushgrass, is a species of grass found in North America. It is listed as endangered in Connecticut., Maryland, New York (state), and Pennsylvania. It is listed as threatened in Kentucky.