Jepson Flora Project: Jepson Interchange    

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Jepson Interchange (more information)
©Copyright 1993 by the Regents of the University of California

  • Up-to-date information about California vascular plants is available from the Jepson eFlora.



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.



Dieter H. Wilken

Stems 1–15, generally solitary, sometimes tufted, glabrous to puberulent
Leaves ± basal; collar glabrous to puberulent; ligule < 1 mm, membranous; blade thread-like, flat to rolled
Inflorescence panicle-like
Spikelet bisexual, 3–5 mm; glumes > lower floret, translucent, keel scabrous; callus short-bristly; axis breaking above glumes and between florets; florets 2; lemma faintly 3–5-veined, generally glabrous, tip with 2 slender teeth, slightly scabrous, awned at or below the middle, awn bent once, exserted (sometimes reduced or 0 in lower floret); palea slightly < lemma
Species in genus: ± 10 species: s Eur
Etymology: (Greek: a grass)


A. praecox L.

Stems 1–12, 5–25 cm, generally glabrous
Leaf: sheath glabrous to slightly scabrous; ligule slightly scabrous
Inflorescence < 1 cm wide, narrow
Spikelet generally 4 mm; glumes 2–3 mm; lemmas ± 2 mm; awns 3–4 mm
Chromosomes: 2n=14
Ecology: Sandy soils, open sites
Elevation: < 100 m.
Bioregional distribution: North Coast, s Outer North Coast Ranges
Distribution outside California: to British Columbia, eastern US; native to s Europe

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