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. condensatus (C. Presl) Á. Löve

Plant cespitose; rhizomes 0 or short
Stem 11–30 dm, glabrous
Leaf: blade 10–28 mm wide
Inflorescence 17–44 cm, panicle-like; lower nodes short-branched; spikelets sessile or stalked
Spikelets: glumes 6–16 mm, awl-like; lemmas 7–14 mm, glabrous to hairy, acute to awn-tipped, awn < 4 mm
Chromosomes: 2n=28,56
Ecology: Dry slopes, open woodland
Elevation: < 1500 m.
Bioregional distribution: Central Western California, Southwestern California, Mojave Desert
Distribution outside California: Mexico
Flowering time: Jun–Aug
Synonyms: Elymus c. C. Presl
Hybridizes with L. triticoides (see L. X multiflorus ).
Horticultural information: DRN: 7, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 &IRR: 8, 9, 10, 11, 12; CVS.