Imperata brasiliensis Trin.
Family Poaceae, Tribe Andropogoneae
Brazilian satintail, Brazilian blady grass
Spikelets subterete, 3.5–5 mm long (excluding callus hairs), of 1 fertile floret and 1 (usually absent) basal sterile lemma. Spikelet callus with silky hairs 7–13 mm long. Glumes 2.4–4.5 mm long, lanceolate, pointed. Sterile lemma (if present) ca. 1 mm long, hyaline. Fertile lemma and palea shorter than glumes, hyaline. Styles 1.1–4.7 mm long, persistent, at least in part. Caryopsis oblanceolate, 0.8–1.5 mm long.
Imperata brasiliensis is often confused with Imperata cylindrica (L.) Räusch.
Molecular diagnostic tools have also been used to distinguish these species.
South America, Central America, Mexico, and the West Indies, United States
low altitudes, sandy and humid soils, pinelands; a weed of waste places and perennial crops
Imperata brasiliensis is an erect, tufted perennial grass with rhizomes, to 100 cm tall. It is abundant and weedy in Brazil; invading soybeans and Yerba mate (Ilex paraguariensis A. St.-Hil., which is used as tea.).
caryopses in side view (upper left), dorsal view (upper right), and ventral view (lower right); photo by Mark Thurmond