Jepson Flora Project: Jepson Interchange    

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

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

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.

LEYMUS

Mary E. Barkworth

Perennial, generally from rhizomes
Leaf: ligule membranous; blade flat or rolled, strongly ribbed above, glabrous or hairy
Inflorescence generally spike-like (panicle-like in L. condensatus), dense, generally > upper cauline leaves; some nodes with 2+, generally sessile spikelets
Spikelet: glumes < spikelet, lanceolate, membranous, flexible or narrowly lanceolate to awl-like, stiff; axis breaking above glumes and between florets; florets 2–7; lemma acute to short-awned; palea < lemma; anthers 2.5–7 mm
Species in genus: 31 species: North America., Eurasia
Etymology: (Anagram of Elymus)
Reference: [Barkworth & Atkins 1984 Amer J Bot 71:609–625]
Some species important in revegetation, often on saline soils. Sometimes treated in Elymus.

Native

L. pacificus (Gould) D.R. Dewey

Plant from rhizomes
Stem 1–6 dm, glabrous or sparsely hairy near nodes
Leaf: blade 10–30 cm, 2–4 mm wide, often > inflorescence
Inflorescence 2–8 cm; spikelets often 1 per node
Spikelet: glumes 5–10 mm, awl-like; lemmas ± 10 mm, generally glabrous, pointed or short-awned
Chromosomes: 2n=28
Ecology: Coastal bluffs
Elevation: < 100 m.
Bioregional distribution: s North Coast, Central Coast, n Channel Islands
Synonyms: Elymus p. Gould
Fls infrequently, seldom collected
Horticultural information: STBL.

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