Bouteloua trifida Thurb., red grama 
DESCRIPTION 
Warm-season , weak perennial. 
Height: 5 to 10 inches. 
Leaf blade : Short; narrow; flat or rolled; surface slightly 
rough ; scattered long hairs on margin. 
Leaf sheath: Shorter than internodes; smooth or slightly 
rough. 
Ligule: Ring of short hair. 
Stem: Smooth; young plants erect, old plants bent at base; 
nodes naked and darker than rest of stem. 
Seedhead: 3 to 7 spikes per seedhead ; about 12 spikelets per 
spike; rachis hairy; fertile lemma of each spikelet tipped 
with 3 short awns. 
GROWTH CHARACTERISTICS 
Growth starts in spring when daytime temperature is about 
70° F. and moisture is adequate. Seed mature 6 weeks after 
growth starts. Because of this characteristic, red grama is often 
referred to as 6 weeks’ grama. Reproduces from seed. Has a shal- 
low root system. Becomes semidormant during summer. 
DISTRIBUTION 
West Texas and Oklahoma, Arizona, southern California, and 
south to central Mexico. 
SITE ADAPTATION 
Adapted to shallow, gravelly, stony soils in southwest Texas 
that have a poor soil-moisture relationship. Invades deep, loamy 
soils denuded by overgrazing. 
USE AND MANAGEMENT 
Red grama is grazed by all livestock. Forage production is low 
but quality is good when plants are green. After seedheads ap- 
pear, nutritive value declines rapidly. This grass helps to protect 
soil from wind and water erosion if lightly grazed. 
Growing points and basal leaves are so close to the ground that 
most livestock cannot harvest more than 50 percent of current 
year’s growth by weight. Deferred grazing during growing sea- 
son every 2 to 3 years maintains plant vigor and allows plants to 
mature seed for maintaining a stand. This grass is seldom a key 
management species excppt on ranges where it grows in almost 
pure stands. 
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