TREATMENT FROM THE JEPSON MANUAL (1993) |
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Jepson Interchange (more information) |
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©Copyright 1993 by the Regents of the University of California
For up-to-date information about California vascular plants, visit the Jepson eFlora. |
AND IS MAINTAINED FOR ARCHIVAL PURPOSES ONLY |
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) 1many; 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: 650900 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.
Annual, perennial herb, often glandular; glands often wart-like, circular, pitted
Leaf: sheath margin hairy on sides just below collar; ligules ciliate
Inflorescence generally panicle-like, open or dense, sometimes spike-like, often glandular
Spikelet laterally compressed; glumes ± unequal, acute or acuminate, 1(3)-veined; florets 3many, axis breaking above glumes and between florets (or persistent with glumes and lemmas deciduous, paleas remaining attached or not); lemma keeled or rounded, acute or obtuse, 3-veined, veins generally obvious; palea ± = lemma
Fruit lens-shaped or elliptic, sometimes grooved, generally red-brown
Species in genus: ± 300 species: tropical, warm temp
Etymology: (Greek: eros, love, agrostis, a kind of grass)
Reference: [Koch 1974 Ill Biol Monogr 48:174]
Native |
Annual
Stem erect, sometimes abruptly bent at base, 1.56(7.5) dm
Leaf: sheaths generally < internodes, glabrous except white- hairy-tufted at collar margins; blade 215(20) cm, 1.53(5) mm wide, flat, glabrous
Inflorescence (5)1025 cm, 312(15) cm wide, open; primary branches spreading or ascending, straight, alternate or opposite; spikelet stalks spreading or appressed
Spikelet 58(10) mm, 1.22 mm wide, generally linear; glumes thin, lower 0.51 mm, upper 11.5 mm; axis not breaking apart, paleas persistent; florets 515(20); lemma 1.52 mm, membranous, gray-green or red-tinged near tip, veins prominent
Fruit ± 1 mm, oblong to slightly pear-shaped, not grooved
Ecology: Open disturbed sites, fields
Elevation: < 1400 m.
Bioregional distribution: California
Distribution outside California: widespread US, to Caribbean, C.America