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Urochloa arizonica - Arizona signalgrass

Scientific Family
Poaceae
Synonyms
Brachiaria arizonica, Panicum arizonicum
Plant type
Grasses
Riparian
No

Grass Description

Origin
Native
Season
Warm

Found on open rocky slopes, in sandy washes and canyon bottoms.

Plant Community
Desert Scrub
Grasslands
Interior Chaparral
Pinyon Juniper Woodlands
Low elevation
1000
High elevation
5500

General Description

Annual grass that is much-branched at the base. Stems branch from the lower nodes and are 4 to 24 inches long. Stems may be erect or sprawl along the ground with ascending tips.

Tufted annual grass up to 2 feet; stems bent at base, nodes swollen, sometimes rooting; seedheads spikelike, spikelets in 2 rows; awnless spikelets are 2-flowered, 1 sessile and sterile, 1 stemmed and fertile; glumes noticeably unequal.

Grass type
Annual
Rhizomes
No
Stolons
No
Clump Diameter 2 ft or more
No
Bushy - highly branched
Yes
Height with Seedheads
12 inches or more
Seedhead Structure
Branched - contracted
Seedhead droops
No
First bloom month
June
Last bloom month
October

Flower Characteristics

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

Seedhead is 2-3/4 to 8 inches tall with appressed or erect-spreading hairs. Spikelet stalks are paired and appressed; spikelets are 2-flowered, the first floret is sterile and the second floret is fertile.

Vegetative Characteristics

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

Blades are flat, 2 to 6 inches long and up to 1/2 inch wide. Leaves may be smooth or rough and are hairy on the margins near the base.

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

Not available.