This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol1", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
307. 1760. [Leersia Soland.; Sw. Prod. 21. 1788. Not Hedw. 1782.]
Marsh grasses with flat narrow generally rough leaf-blades, and paniculate inflorescence. Spikelets 1-flowered, perfect, strongly flattened laterally, and usually more or less imbricated. Scales 2, chartaceous, the outer one broad and strongly conduplicate, the inner much narrower. Stamens 1-6. Styles short, distinct. Stigmas plumose. Grain ovoid, free. [Greek, in reference to the supposed resemblance of these grasses to Millet.]
Spikelets oblong, their width less than one-half their length, somewhat imbricated.
Spikelets 1 1/4 "- 1 1/2" long; panicle-branches usually rigid.
Spikelets 2"-2 1/2" long; panicle-branches generally lax.
Spikelets oval, their width more than one-half their length, much imbricated.
Culms glabrous, decumbent, 1°-3° long, much branched, slender, smooth. Sheaths usually shorter than the internodes; ligule short; blades 2'-6' long, 1 "-8" wide, acute, usually narrowed toward the base, scabrous; terminal panicle finally long-exserted, 3'-8' long, its branches generally spreading, usually naked below the middle; lateral panicles smaller and usually included; spikelets 1 1/4"-1 1/2" long, about \" wide, oblong, appressed; outer scale hispid on the keel and margins; inner scale hispid on the keel; stamens 1 or 2.
Phalaris oryzoides L. Sp. PI. 55. 1753.
Homalocenchrus oryzoides Poll. Hist. PI. Palat. 1: 52. 1776.
Leersia oryzoides Sw. Prodi". 21. 1788.
Culms glabrous, decumbent, 1°-4° long, much branched, rather stout, smooth. Sheaths shorter than the internodes, very rough; ligule very short; blades 3'-10' long, 2"-$" wide, acute, narrowed toward the base, scabrous; terminal panicle 5'-9' long, finally long-exserted, its branches lax, naked at the base, at first erect, later more or less widely spreading; lateral panicles generally included; spikelets 2"-2 1/2" long, about 3/4" wide, elliptic; scales pubescent, the outer one hispid on the keel and on the margins; inner scale much narrower, hispid on the keel; stamens 3; anthers yellow.
In swamps and along streams, often forming dense tangled masses, Newfoundland to Oregon, south to Florida and Texas. Also in the temperate parts of Europe and Asia. False grass. Rice's-cousin. Aug.-Sept.
Culms glabrous, erect, 2°-4° tall, usually simple, smooth. Sheaths shorter than the internodes, scabrous; ligule very short; blades 4'-12' long, 4"-10" wide, acute, more or less narrowed at the base, scabrous; panicle 4 1/2'-9' long, finally exserted, its branches lax, naked below, at first erect, later spreading; spikelets much imbricated, 2"-2 1/2" long, l"-1 3/4" wide, broadly oval; scales smooth or sparingly hispid-scabrous, the outer one strongly 3-nerved, hispid on the keel and margins, the inner much narrower, strongly 1-nerved, hispid on the keel; stamens 2.
Wet grounds. Virginia to Minnesota, south to Florida and Texas. July-Sept.