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

Achnatherum occidentale (Thurb.) Barkworth
Western Needle Grass (stiff needlegrass; Velvet-leaf; western needlegrass)
Poaceae (Grass family)

Introduction to Vascular Plants

© Frank Lomer  Email the photographer   (Photo ID #27561)

E-Flora BC Static Map
Distribution of Achnatherum occidentale
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SUBTAXA PRESENT IN BC
Achnatherum occidentale ssp. pubescens

Species Information

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General:
Perennial tufted grass from fibrous roots; stems 30-120 cm tall, the nodes and internodes smooth to densely hairy.
Leaves:
Lower sheaths smooth to hairy, often fringed at the throats, brown to grey when old; blades to 3 mm wide, usually straight and upright; lower ligules 0.2-1.5 mm long, often fringed along the margins; upper ligules 0.3-1 (1.5) mm long.
Flowers:
Inflorescence a narrow panicle 8-30 cm long; glumes almost equal, 9-15 mm long, green, smooth; lemmas 6-7.5 mm long, hairy, the hairs 0.2-0.5 mm long, hairs at the tips similar in length to those at the base of the awns, the awns 15-40 mm long, twice bent, the first 2 segments with short hairs to long, soft, straight hairs, some of the hairs 0.5-1 mm long; paleas 2/5-3/5 as long as the lemmas, the calluses 0.8-1.2 mm long, sharp.

Source: The Illustrated Flora of British Columbia

Habitat / Range

Dry rocky slopes and open forests in the steppe and montane zones; infrequent in SC and SE BC; S to WY, AZ, and CA.

Source: The Illustrated Flora of British Columbia

Ecology

Ecological Framework for Achnatherum occidentale

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) 280 942 2101
Slope Gradient (%) 0 21 230
Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]
0 199 360
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
0 3 7
Modal Nutrient Regime
Class
C
Number of field plots
 species was recorded in:
590
Modal BEC Zone Class
IDF
All BEC Zones (# of stations/zone) species was recorded in: AT(3), BG(50), BWBS(3), ESSF(27), ICH(13), IDF(284), MS(43), PP(92), SBPS(1), SBS(33)

Synonyms and Alternate Names

Stipa occidentalis

Taxonomic and Nomenclatural Links

Additional Photo Sources

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General References