Jepson Interchange (more information)
Print edition is available from the University of California Press
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This page is based on the 1993 Jepson Manual.
Please see the Jepson eFlora for up-to-date information about California vascular plants. |
| Jepson Flora Project: Jepson Interchange |
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TREATMENT FROM THE JEPSON MANUAL |
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Jepson Interchange (more information) |
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©Copyright 1993 by the Regents of the University of California
Print edition is available from the University of California Press |
| The second edition of The Jepson Manual (2012) is available from the University of California Press | |
| See also the Jepson eFlora, which parallels the Second Edition |
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).[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.
Species in genus: 1 sp
Etymology: (Greek: hard grass, from thick glumes)
| Introduced |
Annual
Stems generally clumped, prostrate to erect on same plant, 2–8 cm
Leaves basal and cauline; sheath generally open; ligule < 2 mm, membranous, obtuse, tip toothed; blade 2–3 cm, flat
Inflorescence spike-like, 1–2 cm
Spikelets 6–10 mm, subsessile, crowded, 2-ranked on 1 side of axis, breaking below glumes, falling as 1 unit (sometimes weakly breaking between florets); glumes and lemmas firmly membranous at base, distal margin translucent; glumes << lower lemmas, unequal, rounded, lower ± 2 mm, generally 3-veined, upper 4–6 mm, 7–9-veined; florets 3–5, lower 2–3 bisexual, upper staminate or sterile; lemmas 3–7 mm, strongly keeled, obtuse, 5-veined, awn 0; palea < lemma
Chromosomes: 2n=14
Ecology: Disturbed sites
Elevation: 700–800 m.
Bioregional distribution: w High Cascade Range (Shasta Valley)
Distribution outside California: to Washington, Colorado, Texas; native to s Europe
| YOU CAN HELP US make sure that our distributional information is correct and current. If you know that a plant occurs in a wild, reproducing state in a Jepson bioregion NOT highlighted on the map, please contact us with that information. Please realize that we cannot incorporate range extensions without access to a voucher specimen, which should (ultimately) be deposited in an herbarium. You can send the pressed, dried collection (with complete locality information indicated) to us (e-mail us for details) or refer us to an accessioned herbarium specimen. Non-occurrence of a plant in an indicated area is difficult to document, but we will especially value your input on those types of possible errors (see automatic conversion of distribution data to maps). |
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