E-Flora BC: Electronic Atlas of the Flora of British Columbia

Hesperostipa comata (Trin. & Rupr.) Barkworth
needle-and-thread grass (needle and thread)
Poaceae (Grass family)

Introduction to Vascular Plants

© Jamie Fenneman  Email the photographer   (Photo ID #25213)

E-Flora BC Static Map
Distribution of Hesperostipa comata
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Species Information

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General:
Perennial, tufted grass from fibrous roots; stems erect, 30-70 cm tall.
Leaves:
Sheaths smooth to rough, strongly ribbed, not fringed along the margins; blades in-rolled and 0.5-2 mm wide, or if flat, up to 4 mm wide; ligules of the upper leaves to 7 mm long, usually pointed, sometimes jagged at the tips.
Flowers:
Inflorescence a loose, but narrow panicle, 10-28 cm long, the branches ascending; glumes narrow, nearly equal, papery; lower glumes 18-35 mm long, upper glumes 1-3 mm shorter; lemmas 7-13 mm long, evenly covered with 1 mm-long white hairs or smooth across the back of the lemma, awned, the awns firm and straight or zig-zagged and curved, 5-30 cm long; calluses 2-4 mm long, hairy.
Notes:
Two subspecies occur in BC:

1. Terminal segment of the awn firm, straight or almost so, usually less than 5.5 cm long.................... ssp. intermedia (Scribn. & Tweedy) Barkw.

1. Terminal segment of the awn zig-zagged, curved, usually more than 5.5 cm long................... ssp. comata

Source: The Illustrated Flora of British Columbia

Habitat / Range

Dry, open grassy slopes in the steppe and montane zones; common in SC and SE BC, infrequent northward; N to YT, E to PQ and S to NY, MI, IL, IA, TX, NM, AZ and CA.

Source: The Illustrated Flora of British Columbia

Ecology

Ecological Framework for Hesperostipa comata

The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)

Site Information
Value / Class

Minimum

Average

Maximum

Elevation (metres) 409 712 1026
Slope Gradient (%) 3 21 55
Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]
52 207 270
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
0 1 3
Modal Nutrient Regime
Class
B
Number of field plots
 species was recorded in:
10
Modal BEC Zone Class
PP
All BEC Zones (# of stations/zone) species was recorded in: BG(4), IDF(2), PP(4)

Climate

The climate type for this species, as reported in the: "British Columbia plant species codes and selected attributes. Version 6 Database" (Meidinger et al. 2008), is not evaluated, unknown or variable.

Taxonomic and Nomenclatural Links

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