Achnatherum nelsonii (Scribn.) Barkworth
Columbia Needle Grass (Columbia needlegrass)
Poaceae (Grass family)

Introduction to Vascular Plants

Photograph

© Jamie Fenneman     (Photo ID #25117)


Map

E-Flora BC Static Map

Distribution of Achnatherum nelsonii
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Species Information

General:
Perennial tufted grass from fibrous roots; stems 40-175 cm tall.
Leaves:
Sheaths open, smooth to densely hairy, the margins sometimes with a fringe of hairs; blades (0.5) 1.2-5 mm wide; lower ligules 0.2-0.7 mm long, thin and flexible, blunt to rounded, usually without hairs along the margins; upper ligules up to 1.5 mm long, pointed.
Flowers:
Inflorescence a narrow panicle, 9-36 cm long, the branches straight, appressed to ascending, the spikelets appressed to the branches; florets not flattened; glumes 6-12.5 mm long, smooth; lemmas 6-7.5 mm long, smooth above, short-hairy below, the hairs 0.2-0.5 mm long, the tips minutely lobed, membranous, 0.1-0.4 mm long, awned, the awns 19-31 mm long, the first segments rough or short-hairy, persistent; paleas 2-4 mm long, 1/3-1/2 as long as the lemmas, the calluses 0.2-1 mm long, blunt, the smooth areas barely extending beyond the base of the callus hairs.

SourceThe Illustrated Flora of British Columbia

Ecology

Ecological Framework for Achnatherum nelsonii

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

Avg

Min

Max

Elevation (metres)
1085 529 2246
Slope Gradient (%)
19 0 115

Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]

201 0 345
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
2 0 5
Modal Nutrient Regime
Class
C
# of field plots
 species was recorded in:
210
Modal BEC Zone Class
IDF

All BEC Zones (# of stations/zone) species was recorded in

BG(1), ESSF(15), ICH(7), IDF(122), MS(24), PP(37)

Habitat and Range

Mesic to dry rocky slopes and open forests from the lowland to subalpine zones; frequent in NE, WC, SC and SE BC; N to YT, E to SK and S to TX, NM, AZ and CA.

SourceThe Illustrated Flora of British Columbia

Synonyms

Synonyms and Alternate Names:
Stipa nelsonii