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Sporobolus contractus - spike dropseed

Scientific Family
Poaceae
Synonyms
Sporobolus cryptandrus var. strictus, Sporobolus strictus
Plant type
Grasses
Riparian
No

Grass Description

Origin
Native
Season
Warm

Dry open sandy or rocky slopes and washes, frequent along roadsides. Found occasionally in desert scrub, desert grasslands, and pinyon-juniper woodlands.

Plant Community
Desert Scrub
Disturbed Areas
Interior Chaparral
Pinyon Juniper Woodlands
Grasslands
Low elevation
2500
High elevation
6500
Similar species
Sporobolus cryptandrus, S. flexuosus

General Description

Tufted very erect perennial grass, stems 3 to 4 feet tall, small clusters to large clumps.

Tufted erect perennial up to 4 feet tall. Collar and ligule are hairy. Blades smooth, flat or involute. Seedhead contracted, dense, remains spikelike at maturity, basal portion enclosed in leaf sheath. Spikelets 1/16 inch long, one flowered, not awned.

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
June
Last bloom month
September

Flower Characteristics

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

Seedhead dense and contracted, spikelike, typically less than 1/2 inch thick, 6 to 22 inches long. Sometimes the entire seedhead remains enclosed in the sheath. Glumes unequal.

Vegetative Characteristics

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

Blades 4 to 12 inches long, 1/8 to 1/2 inch wide, flat to rolled inward, tapering to a slender tip. Smooth on both surfaces, margins whitish, somewhat rough.

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

Fair to good.