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.

SPOROBOLUS

DROPSEED, SACATON

Michael Curto

Annual, perennial herb
Stems generally ascending to erect, 2–20 dm, generally tufted, ± solid in X -section
Leaves generally basal; cauline few, ascending or curving away; distal sheath margin and collar glabrous or hairy; ligule < 1 mm, hairy or membranous, fringed; blade flat to inrolled, generally glabrous or scabrous, sometimes short-soft-hairy
Inflorescence terminal, also sometimes axillary, panicle- or spike-like, generally partly enclosed by sheath; branches spreading or appressed
Spikelet < 6 mm, generally pale to gray-green or purplish; glumes generally unequal, upper < or > lemma, membranous to translucent, 1-veined; floret bisexual, generally breaking above glumes; lemma texture generally like glumes, 1(3)-veined; palea < or > lemma
Fruit 1–3 mm, generally falling from floret, generally gelatinous when wet
Species in genus: ± 150 species: Am, Eurasia, Africa
Etymology: (Greek: to throw seed, from deciduous seeds)

Native

S. cryptandrus (Torr.) A. Gray

SAND DROPSEED

Perennial
Stems tufted, 3–10 dm
Leaf: distal sheath margin glabrous to short-hairy; collar margin glabrous to densely long-hairy; ligule < 0.5 mm, hairy; blade 3–15 cm, 1–5 mm wide
Inflorescence generally terminal, 0.8–3(4) dm; base 2–6(10) cm wide, panicle-like, pyramid-shaped or oblong in outline, ± open, sometimes completely enclosed by sheath; lower 1° branches generally > 3 cm, ± spike-like; 2° and 3° branches appressed
Spikelet 1.5–2.5 mm; glumes, lemma keeled; glumes unequal, lower 0.5–1 mm, ± awl-like, upper > 0.5 X lemma, narrowly lanceolate, acute; lemma 1.5–2.5 mm, ovate to narrowly lanceolate, acute; palea ± = lemma; anthers 0.2–1 mm
Fruit ± 1 mm
Chromosomes: 2n=18,36,38,72
Ecology: Rocky to sandy washes, slopes, scrub, woodland
Elevation: 350–2800 m.
Bioregional distribution: east-central High Sierra Nevada, San Bernardino Mountains, Peninsular Ranges, East of Sierra Nevada, Desert (used for revegetation elsewhere)
Distribution outside California: widespread s Canada, US, n Mexico
Flowering time: May–Oct
Horticultural information: SUN, DRN: 1, 2, 3, 7, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24; also STBL.