Bulbous Bluegrass

Bulbous Bluegrass, Courtesy of Richard Shaw, Intermountain Herbarium

© Intermountain Herbarium. Photo courtesy of Richard J. Shaw, Intermountain Herbarium. http://herbarium.usu.edu/
Common Name(s):

Bulbous bluegrass
Winter bluegrass

Scientific Name:

Poa bulbosa L.

Symbol:

POBU

Description:

Life Span: Short-lived perennial
Origin: Introduced
Season: Cool

 

Growth Characteristics: Introduced from Eurasia, this grass grows 12-24 inches tall. The panicle is egg-shaped, compact or open at flowering, 2-4 inches long and somewhat nodding after development of florets. Reproduces from bulblets which sprout from the parent plant and from basal bulbs. Plant initiates growth early in the spring (April to June) and therefore cures early.

Seedhead: Florets form true bulblets with dark purple bases; spikelets 3-6-flowered; glumes equal, 2-3 mm long; glumes extending into slender green tips 1/8-5/8 inches long. Bulblets require a significant dormant period for germination.

 

Leaves: Leaves are basal, flat to loosely rolled with tips arrow-shaped; 0.5-3 mm wide, 2-6 inches long; sheaths open; nodes swollen; auricles absent; ligules membranes, 1/8 inch long

Stems: Solitary to dense tufts (caespitose).

Ecological Adaptations:

Bulbous bluegrass can become established in fairly unproductive sites; found along trails, roadsides, or other disturbed sites at elevations ranging from 3940 to 9840 feet. Bulbous bluegrass is not an aggressive or competitive species in well developed crops, pastures and native, undisturbed areas.

 

Soils: Adapted to a wide variety of soils from shallow to deep and from sands to clays. It grows well in infertile soils high in gravels, stones, and cobbles.

Associated Species: Kentucky bluegrass, bluebunch wheatgrass, cheatgrass brome, chokecherry, and sagebrush.

Uses and Management:

Bulbous bluegrass has been used in seeding eroded areas where rapid establishment of plant cover is needed. Plants are preferred and nutritious to wildlife and livestock in early spring until they flower. Early, heavy grazing can be used as a tool to reduce the productions and spread of individual bulblets.