POACEAE

GRASS FAMILY

James P. Smith, Jr., except as specified

Annual to bamboo-like; roots generally fibrous
Stem generally round, hollow; nodes swollen, solid
Leaves alternate, 2-ranked, generally linear; sheath generally open; ligule membranous or hairy, at blade base
Inflorescence various (of generally many spikelets)
Spikelet: glumes generally 2; florets (lemma, palea, flower) 1–many; lemma generally membranous, sometimes glume-like; palea generally ± transparent, ± enclosed by lemma
Flower generally bisexual, minute; stamens generally 3; stigmas generally 2, generally plumose
Fruit: achene-like grain
Genera in family: 650–900 genera; ± 10,000 species: worldwide; greatest economic importance of any family (wheat, rice, maize, millet, sorghum, sugar cane, forage crops, ornamental, weeds; thatching, weaving, building materials)
Reference: [Hitchcock 1951 Manual grasses US, USDA Misc Publ 200; Clayton & Renvoise 1986 Kew Bull Add Series 13]
See Glossary p. 26 for illustrations of general family characteristics. Generally wind-pollinated.

STENOTAPHRUM

Robert Webster

Annual, perennial herb
Stems prostrate to ascending, generally compressed; internode solid to spongy inside
Leaves cauline; ligule mostly hairy, membrane < 0.5 mm; blade folded
Inflorescence raceme- to panicle-like; 1° branches appressed, axis straight or wavy, tip awl-like; spikelets short-stalked to embedded in axis, subtended by 1+ bristles
Spikelet compressed, generally falling as 1 unit, sometimes with inflorescence axis; glumes equal to unequal; florets 2, lower floret sterile or staminate, lemma ± = upper glume, upper floret bisexual, lemma thick, firm, smooth or minutely rough, margin flat or inrolled, tip blunt
Species in genus: 7 species: tropical worldwide
Etymology: (Greek: narrow trench, from spikelet scars on inflorescence axis)
Reference: [Sauer 1972 Brittonia 24:202–222]