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



Paul M. Peterson

Annual, perennial herb, sometimes mat-like, often rhizomed
Stem decumbent to erect, ± clumped
Leaves basal and cauline; sheath open; ligule membranous, entire to irregularly toothed, sometimes with 1 large tooth on each side; blade flat to rolled
Inflorescence panicle-like, narrow to open; branches spreading to appressed
Spikelet: glumes subequal, generally 1-veined, short-pointed to awned, upper glume sometimes 3-veined; florets 1, sometimes 2, breaking above glumes; lemma short-pointed to awned, glabrous to hairy, 3-veined; palea < to = lemma
Fruit ± fusiform, reddish brown, generally falling with lemma and palea
Species in genus: ± 160 species: temp Am, s Asia
Etymology: (H.L.E. Muhlenberg, Pennsylvania botanist, 1753–1815)
Reference: [Reeder 1981 in Gould and Moran 1981 San Diego Soc Nat Hist Memoir 12:67–78]
Horticultural information: STBL.


M. rigens (Benth.) Hitchc.


Stem densely clumped, 5–15 dm
Leaf: ligule 0.5–2 mm, truncate, ± ciliate; blade 10–50 cm, 1.5–6 mm wide, flat
Inflorescence 15–60 cm, 5–12 mm wide, cylindric, narrow; branches appressed, densely flowered
Spikelet: glumes 1.8–3 mm, acute or obtuse, ± scabrous; lemma 2.5–3.5 mm, base sparsely short-hairy, ± abruptly pointed; anther 1.3–1.7, yellow to purple
Chromosomes: 2n=40
Ecology: Sandy to gravelly places, canyons, stream bottoms
Elevation: < 2150 m.
Bioregional distribution: High Cascade Range, Sierra Nevada, Great Central Valley, Outer South Coast Ranges, South Coast, Transverse Ranges, San Jacinto Mountains, East of Sierra Nevada, Mojave Desert
Distribution outside California: to Texas, Mexico
Flowering time: Jun–Sep
Horticultural information: 6, 14, 15, 16, 17, 22, 23, 24; IRR: 1, 2, 3, 7, 8, 9, 10, 11, 18, 19, 20, 21.

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