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Achnatherum nelsonii - Columbia needlegrass

Scientific Family
Poaceae
Synonyms
Stipa columbiana, Stipa nelsonii, Stipa occidentalis
Other common names
Subalpine needlegrass
western needlegrass
Plant type
Grasses
Riparian
No

Grass Description

Origin
Native
Season
Cool

Openings in upper sagebrush zones, mountain brush, pinyon-juniper and aspen-fir communities.

Plant Community
Interior Chaparral
Montane Conifer Forest
Pinyon Juniper Woodlands
Low elevation
5000
High elevation
8000
Similar species
Achnatherum robustum

General Description

Perennial bunchgrass that grows in dense, leafy tufts. Roots are deep and fibrous and can extend vertically to more than 3 feet deep.

Lemmas have long slender somewhat sparse hairs. Awn mostly more than 1 inch long. Sheaths not hairy at the collar. Lower nodes of panicle without hairs. Blades are long and bright green.

Grass type
Perennial bunchgrass
Rhizomes
No
Stolons
No
Clump Diameter 2 ft or more
No
Bushy - highly branched
No
Height with Seedheads
24 inches or more
Seedhead Structure
Branched - contracted
Seedhead droops
No
First bloom month
June
Last bloom month
September

Flower Characteristics

Flowers per Spikelet
One-flowered
Spikelets One-Sided
No
Awns
Greater than 1 inch
Three Awns
No
Awns bent
Yes
Flower and Seedhead Notes

The seedhead is a dense, slender, spike-like panicle or raceme. Awns twice-bent, first 2 segments are hairy.

Vegetative Characteristics

Blade is hairy
No
Blade margins white
No
Blade cross-section
Flat

Leaves are flat when green and rolled at the margins when dry, 4 to 10 inches long, sometimes longer and less than 1/4 inch wide.

Sheath is hairy
No
Tufts of hair top of sheath or collar
No
Ligule
Membranous
Auricles
No

This is a palatable grass to domestic livestock such as cattle, horses and sheep. It is also consumed by mule deer. However, when the awns mature, it becomes undesirable to most animals.