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Sporobolus giganteus - giant dropseed

Scientific Family
Poaceae
Plant type
Grasses
Riparian
Yes

Grass Description

Origin
Native
Season
Warm

Grasslands, woodlands, sandy hills, sandy areas along rivers and roadsides.

Plant Community
Disturbed Areas
Grasslands
Pinyon Juniper Woodlands
Riparian
Low elevation
4000
High elevation
6000

General Description

Tall robust and coarse bunchgrass, 3 to 7 feet tall. Stems have thick bases and tufts of white hairs at the tips of the leaf sheaths.

Tall and robust perennial bunchgrass; wide blades; seedhead contracted, spike-like; sheaths conspicuously hairy on margins and collar; spikelets are pedicellate and laterally compressed, less than 1/8 inch long.

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
August
Last bloom month
October

Flower Characteristics

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

Seedhead is a dense spike up to 2-1/2 feet tall that is usually included in the uppermost sheath. Branches are appressed or spreading and spikelet-bearing to the base. Spikelets have one fertile floret.

Vegetative Characteristics

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

Blades are 4 to 20 inches long and less than 1/2 inch wide. Leaves are flat, involute or folded and smooth with whitish margins and rough edges.

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

Early growth provides considerable forage for livestock. However, palatability declines rapidly with maturity.