Jepson Flora Project: Jepson Interchange    

link to manual TREATMENT FROM THE JEPSON MANUAL (1993) previous taxon | next taxon
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.


Mary E. Barkworth

Perennial, cespitose
Stem erect, unbranched
Leaf: blade upper surface conspicuously ridged, generally inrolled
Inflorescence panicle-like, narrow
Spikelet: glumes tapered from near base to acute tip, awn 0; axis breaking above glumes; floret 1, 7–25 mm, narrowly cylindric; callus 2–5 mm, sharp, densely stiff-hairy; lemma hard, margins overlapping at maturity, upper portion fused, awn 6.5–18 cm, bent twice, lower segments twisted, last segment not twisted; palea = lemma, hard, 2-veined, veins terminating at tip
Species in genus: 4 species: North America
Etymology: (Greek: western stipa)
Segregated from Stipa ; most closely related to Piptochaetium, Nassella.


H. comata (Trin. & Rupr.) Barkworth


Stem 1–11 dm
Inflorescence 10–28 cm
Spikelet: lower glume 18–35 mm, upper 1–3 mm shorter; floret 7–13 mm; lemma evenly hairy, hairs ± 1 mm, white; awn 65–195 mm
Ecology: Well-drained soils
Elevation: 200–3500 m.
Bioregional distribution: Sierra Nevada, Transverse Ranges, Peninsular Ranges, Great Basin Floristic Province, Desert Mountains
Distribution outside California: to Yukon, Great Plains, Mexico
Synonyms: Stipa c. Trin. & Rupr.


subsp. comata

Spikelet: awn 75–195 mm, distal segment wavy or curly
Chromosomes: 2n=38,44,46
Ecology: Grassland, sagebrush scrub
Elevation: 200–3500 m.
Bioregional distribution: Sierra Nevada, Transverse Ranges, Peninsular Ranges, Great Basin Floristic Province, Desert Mountains, introduced elsewhere
Distribution outside California: to Yukon, c US, Mexico
Flowering time: Jun–Jul
Horticultural information: DRN, SUN: 1, 2, 15, 16, 17 &IRR: 3, 7, 14, 18, 19, 20, 21, 22, 23, 24; also STBL.

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bioregional map for HESPEROSTIPA%20comata%20subsp.%20comata being generated
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).

Retrieve Jepson Interchange Index to Plant Names entry for Hesperostipa comata subsp. comata
Retrieve dichotomous key for Hesperostipa
Overlay Consortium of California Herbaria specimen data by county on this map
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