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.

VULPIA

Susan G. Aiken and Robert I. Lonard

Annual
Stems < 8 dm, solitary or loosely clumped, ascending to erect, unbranched
Leaves generally cauline; sheath < internode; ligule < 1 mm, membranous, minutely fringed; blade < 15 cm, 0.5–2.5 mm wide, flat or rolled when dry; basal lobes 0
Inflorescence panicle-like, narrow, dense or open
Spikelet: glumes unequal, lanceolate, lower sometimes minute, upper 3-veined; axis breaking above glumes and between florets; florets 2–10, generally cleistogamous; lemma back round, 3–5-veined, awn < 22 mm, straight; palea ± = lemma, tip forked; stamen generally 1, < 1 mm; ovary tip glabrous
Fruit 3–6.5 mm, ± linear, ± sticking to palea
Etymology: (J.S. Vulpius, pharmacist-botanist of Baden, Germany)
Reference: [Lonard & Gould 1974 Madroño 22:217–230]
Horticultural information: STBL.

Introduced

V. myuros (L.) C.C. Gmel.

Stem < 7.5 dm, glabrous or scabrous only near inflorescence
Inflorescence 4–25 cm, < 2 cm wide, ± dense; base often enclosed in sheath at maturity; branches 1–3 per node; spikelet stalk < 1 mm, slender
Spikelet 5–11.5 mm; lower glume generally < 1.5 mm, upper ± 2.5–5.5 mm; florets 3–6; lemma 4.5–6.5, awn 5–15 mm
Fruit 3.5–4.5 mm
Chromosomes: 2n=42
Ecology: Common. Generally open places, sandy soils
Elevation: < 2000 m.
Bioregional distribution: California Floristic Province, Desert
Distribution outside California: worldwide; probably native to Europe

Introduced

var. myuros

Spikelet: lemma margin glabrous near tip, awn of lowermost floret 7.5–17 mm
Ecology: Open places, hillsides, washes, or vernally moist sites in chaparral
Elevation: generally < 1500 m.
Bioregional distribution: California Floristic Province
Distribution outside California: worldwide; probably native to Europe
Synonyms: Festuca m. L