Hesperostipa comata (Trin. & Rupr.) Barkworth (redirected from: Stipa comata)
Family: Poaceae
[Stipa comata Trin. & Rupr.]
Hesperostipa comata image
Robert Sivinski  

Culms 12-110 cm; lower nodes glabrous or pubescent. Lower sheaths glabrous or pubescent, not ciliate; ligules of lower leaves 1-6.5 mm, scarious, usually acute, sometimes trun-cate, often lacerate; ligules of upper leaves to 7 mm; blades 0.5-4 mm wide, usually invol-ute. Panicles 10-32 cm, contracted. Glumes 16-35 mm, 3-5-veined; lower glumes 18-35 mm; upper glumes 1-3 mm shorter; florets 7-13 mm; calluses 2-4 mm; lemmas evenly pubescent, hairs about 1 mm, white, sometimes glabrous immediately above the callus; awns 65-225 mm, first 2 segments scabrous to strigose, hairs shorter than 1 mm, terminal segment scabridulous.

Hesperostipa comata is found primarily in the cool deserts, grasslands, and pinyon-juniper forests of western North America. The two subspecies overlap geographically, but are only occasionally sympatric. Both are primarily cleistogamous.

FNA 2007, Gould 1980

Common Name: needle and thread

Duration: Perennial

Nativity: Native

Lifeform: Graminoid

General: Perennial bunchgrass with stems 12-110 cm tall, lower nodes glabrous or pubescent.

Vegetative: Lower sheaths glabrous or pubescent, blades 0.5-4 mm wide, tightly involute, with ligules of the lower leaves 1-6.5 mm, scarious, acute, often lacerate, with upper ligules to 7 mm.

Inflorescence: Contracted and narrow panicles 10-32 cm, glumes subequal 16-35 mm, 3-5 veined, lower glumes 18-35 mm, upper glumes 1-3 mm shorter, florets 7-13 mm, lemma straw-colored or occasionally brownish, hairs about 1 mm, white, sometimes glabrous immediately above the callus with awns 6.5-23 cm, twice-geniculate, first two segments scabrous to strigose, hairs shorter than 1 mm, terminal segment minutely roughened.

Ecology: Found on sandy or rocky soils from 3,500-7,500 ft (1067-2286 m); flowers May-July.

Notes: Distinctive with the length of the awns and the way the stems tend to curve over at anthesis.

Ethnobotany: The straight fruits were used as play arrows by children.

Etymology: Hesperostipa means western Stipa, while comata means finished with a tuft.

Synonyms: None

Editor: SBuckley, 2010

Tufted, 4-10 dm; sheaths glabrous or nearly so, the upper often inflated over the base of the panicle; ligule 2-5 mm; blades smooth or scaberulous, 1-3 mm wide, usually involute; panicle narrow, 2-3.5 dm, the ascending branches each with 1-few spikelets; glumes 15-35 mm, tapering to a long filiform point; mature lemma 9-14 mm, pale brown, villous at base, villosulous to glabrate above, its awn 9-16 cm, very slender, loosely flexuous or coiled, obscurely once geniculate; 2n=44, 46. Dry plains and prairies, often in sandy soil; widespread in the w. cordillera, extending e. across the Great Plains to Minn. and Io., and irregularly to Mich. and n. Ind. (Hesperostipa c.)

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

©The New York Botanical Garden. All rights reserved. Used by permission.

Hesperostipa comata image
Robert Sivinski  
Hesperostipa comata image
Hesperostipa comata image
Hesperostipa comata image
Hesperostipa comata image
Hesperostipa comata image
Hesperostipa comata image
Cynthia Roché  
Hesperostipa comata image
Hesperostipa comata image
Hesperostipa comata image
Hesperostipa comata image
Hesperostipa comata image
RT Hawke  
Hesperostipa comata image
Dean Wm. Taylor