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Sphenopholis obtusata - prairie wedgescale

Scientific Family
Poaceae
Synonyms
Aira obtusata, Spenopholis obtusata var. lobata, S. obtusata var. pubescens
Other common names
wedge grass
Plant type
Grasses
Riparian
Yes

Grass Description

Origin
Native
Season
Cool

Open woodlands, forests, marshes, moist meadows, stream banks and disturbed areas.

Plant Community
Disturbed Areas
Montane Conifer Forest
Pinyon Juniper Woodlands
Riparian
Low elevation
3000
High elevation
8000

General Description

Annual or short-lived perennial with tufted or solitary stems 8 to 48 inches tall, sheaths are open and smooth or covered with small hairs.

Slender perennial with flat blades and narrow seedheads. Seedhead is dense, often spike-like and erect or nearly so. Second spikelet glume is much wider than the lemmas and rounded at the tip. Spikelets are awnless.

Grass type
Perennial bunchgrass
Rhizomes
No
Stolons
No
Clump Diameter 2 ft or more
No
Bushy - highly branched
No
Height with Seedheads
Greater than 36 inches
Seedhead Structure
Branched - contracted
Seedhead droops
No
First bloom month
April
Last bloom month
June

Flower Characteristics

Flowers per Spikelet
Multi-flowered
Spikelets One-Sided
No
Awns
Absent
Three Awns
No
Awns bent
No
Flower and Seedhead Notes

Contracted, dense seedheads are 2 to 6 inches long, 3/4 inch wide, erect and spike-like. Spikelets are wedge-shaped and laterally compressed.

Vegetative Characteristics

Blade is hairy
Yes
Blade margins white
No
Blade cross-section
Flat
Involute – rolled inward on upper surface

Blades are 2 to 5-1/2 inches long, 1/3 inch wide and usually flat or rarely, slightly involute. Surfaces may be rough or hairy.

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

This grass produces good quality forage for all classes of livestock early in the spring. It is less palatable later in the season.