Culms decumbent and sprawling, rooting at the nodes, distally erect, to 15 dm; sheaths roughly retrorse-scabrous; ligule truncate, to 1 mm; blades very rough-margined with stiff colorless spinules, the main blades 15-30 cm נ6-15 mm; panicles pale green or whitish, the terminal one to 30 cm, exserted or partly included, its slender branches ±spreading when exserted; lower part of the panicle with 2 or 3(4) branches per node; spikelets ascending, 4-7.5 mm, a fourth to a third as wide, imbricate in spike-like clusters of 3-8 ending the branches; lemma pilose, stiffly ciliate on the keel; stamens 3; late-season axillary panicles reduced and ±included in the sheaths; 2n=48. Swamps, wet meadows, and muddy soil; Que. and N.S. to B.C., s. to Calif. and Fla.; Europe; e. Asia. Estuarine plants vary to a flaccid, virtually glabrous phase with included panicles.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
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Jepson 2012, Kearney and Peebles 1969, FNA 2007
Common Name: rice cutgrass Duration: Perennial Nativity: Native Lifeform: Graminoid General: Creeping perennial grass from long, slender rhizomes; stems to 1.5 m tall, decumbent and rooting at the nodes, the terminal portions of the stems erect; nodes soft-hairy with distinctive bands of short white hairs. Vegetative: Blades flat to folded, 10-28 cm long and 8-14 mm wide, the margins and surfaces strongly scabrous, the margins with downward-pointing teeth; sheaths glabrous to minutely scabrous; ligules membranous, to 1 mm long, with truncate apices. Inflorescence: Open and panicle-like with arched to wavy lateral branchlets and spikelet stalks. Spikelets 1-flowered, laterally compressed, glumes absent, lemmas and paleas firmly membranous; lemmas 4-5 mm long, boat-shaped, hispid to strigose on the back, awnless, 5-veined; paleas 3-nerved, much narrower than lemmas, oblong to narrowly elliptic; palea margins firmly held by the margins of the lemmas; spikelets disarticulating from the pedicels. Ecology: Found in marshes, near streams and ponds, to 4,000 ft (1219 m); flowers July-October. Distribution: Widespread and native throughout the United States, s. CAN, n. MEX, Europe and Asia. Introduced to Macaronesia and Australia. Notes: This distinctive creeping grass is found in wet or marshy environments. Look for a diffuse panicle emerging from the upper leaf sheath; single-flowered spikelets that break off at the pedicel, leaving no glumes behind; bands of felty pubescence at most stem nodes; and blades with an obvious midvein on the lower surface. Also be careful of the tiny downward-pointing teeth on the margins of the blades, which are difficult to see but capable of drawing blood from careless handlers, giving the species its common name. Ethnobotany: Unknown. Etymology: Leersia is after German botanist and pharmacist Johann Daniel Leers, and oryzoides means like genus Oryza, rice. Synonyms: Homalocenchrus oryzoides, Phalaris oryzoides Editor: LCrumbacher 2012, AHazelton 2015