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Agrostis idahoensis - Idaho bentgrass

Scientific Family
Poaceae
Other common names
Idaho redtop
Colonial bentgrass
Plant type
Grasses
Riparian
Yes

Grass Description

Origin
Native
Season
Warm
Alpine and subalpine meadows along wet seepage areas and bogs; wet openings with mossy areas in coniferous forests.
Plant Community
Riparian
Low elevation
5500
High elevation
10500

General Description

Stems are erect and slender. Narrow flat leaves are mostly basal. Seedheads appear tufted and are open and spreading.
Panicle open, branches have secondary branches in the lower half; spikelets start at the middle of the branches; palea very short, 1/3 as long as the lemma, 1-flowered spikelets.
Grass type
Perennial bunchgrass
Rhizomes
No
Stolons
No
Clump Diameter 2 ft or more
No
Bushy - highly branched
No
Height with Seedheads
12 inches or more
Seedhead Structure
Branched - open and spreading
Seedhead droops
No
First bloom month
July
Last bloom month
August

Flower Characteristics

Flowers per Spikelet
One-flowered
Spikelets One-Sided
No
Awns
Less than 1/4 inch
Three Awns
No
Awns bent
No
Flower and Seedhead Notes
Seedhead is an open, thin array of wispy branches bearing spikelets. Lower seedhead branches are whorled and flowers are bisexual.

Vegetative Characteristics

Blade is hairy
No
Blade margins white
No
Blade cross-section
Flat
Leaves are mostly basal and clasp the stems. Leaf sheaths are mostly open and smooth. Older leaves are often inrolled.
Sheath is hairy
No
Tufts of hair top of sheath or collar
No
Ligule
Membranous
Auricles
No

Fair to good, especially palatable when young.