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

    THIS PAGE IS NO LONGER UPDATED
    AND IS MAINTAINED FOR ARCHIVAL PURPOSES ONLY
  • Up-to-date information about California vascular plants is available from the Jepson eFlora.

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.

HESPEROSTIPA

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.

Native

H. comata (Trin. & Rupr.) Barkworth

NEEDLE-AND-THREAD


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.

Native

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.

previous taxon | next taxon
bioregional map for HESPEROSTIPA%20comata%20subsp.%20comata being generated
 


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
Show other taxa with the same California distribution | Read about bioregions | Get lists of plants in a bioregion
Return to the Jepson Interchange main page
Return to treatment index page
Glossary


University & Jepson Herbaria Home Page |
General Information | University Herbarium | Jepson Herbarium |
Visiting the Herbaria | On-line Resources | Research |
Education | Related Sites
Copyright © by the Regents of the University of California