TREATMENT FROM THE JEPSON MANUAL	previous taxon | next taxon Jepson Interchange (more information)
	©Copyright 1993 by the Regents of the University of California Print edition is available from the University of California Press

	The second edition of The Jepson Manual (2012) is available from the University of California Press
	See also the Jepson eFlora, which parallels the Second Edition

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). [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.

BROMUS

BROME

Dieter H. Wilken and Elizabeth L. Painter

Annual to perennial herb
Leaves basal and cauline; sheath closed, generally hairy; ligule generally < 5 mm, membranous, entire to fringed; blade flat to inrolled
Inflorescence generally panicle-like, open to dense; spikelet stalk generally stiff, rigid
Spikelet strongly compressed to cylindric; axis breaking above glumes and between florets; glumes unequal, generally < lower floret, lower generally 1–3-veined, upper 3–7-veined, back rounded to keeled, tip acute; lemmas faintly 5–9-veined, tip generally 2-toothed, short-pointed to straight-awned from between teeth; palea generally < lemma
Species in genus: ± 150 species: temp worldwide
Etymology: (Greek: ancient name)
Reference: [Stebbins 1947 Contr Gray Herb 165:42–55; Wagnon 1952 Brittonia 7:415–480]
Native species need careful study.

Introduced

B. inermis Leyss. subsp. inermis

SMOOTH BROME

Perennial 45–100+ cm, rhizomed
Leaf glabrous to sparsely scabrous; blade 5–12 mm wide, margin ± scabrous
Inflorescence 9–20 cm, ± dense; branches generally ascending to erect
Spikelet ± cylindric, glabrous to minutely scabrous; lower glume 5–9 mm, generally 1-veined; upper glume 6–10 mm, generally 3-veined; florets 5–10; lemma body 8–12 mm, 5–7-veined, back rounded, tip obtuse to minutely lobed, awn 0–2.5 mm
Chromosomes: 2n=28,42,± 56
Ecology: Meadows, ditches, fields
Elevation: < 2700 m.
Bioregional distribution: High Sierra Nevada (e slope), Outer South Coast Ranges, South Coast, Peninsular Ranges, Great Basin Floristic Province
Distribution outside California: to e US; native to Europe
Flowering time: May–Aug
Cult widely for forage, revegetation after fire. Ssp. pumpellianus (Scribner) Wagnon with puberulent lemmas is native to nw North America, Rocky Mtns.