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. cinereus (Scribn. & Merr.) Á. Löve

Plant cespitose; rhizomes 0 or short
Stem 7–21 dm, generally glabrous; lowest node often hairy
Leaf: ligule 2.5–6.5 mm; blade 3–12 mm wide, upper surface scabrous
Inflorescence 9–19 cm, unbranched; spikelets 2–17 per node, sessile
Spikelet: glumes 8–18 mm, awl-like; lemma 6.5–12 mm, acute to awn-tipped, glabrous to short-hairy
Chromosomes: 2n=28,56
Ecology: Streamsides, canyons, roadsides, sagebrush scrub, open woodlands
Elevation: < 3000 m.
Bioregional distribution: Cascade Range, Sierra Nevada, Tehachapi Mountain Area, Sacramento Valley, Transverse Ranges, Great Basin Floristic Province, Desert Mountains
Distribution outside California: to Canada, Colorado
Flowering time: Jun–Aug
Synonyms: Elymus c. Scribner & Merr
Hybridizes with L. triticoides.
Horticultural information: TRY.