Cheatgrass
Bromus tectorum · Cool-season annual, C3 grass
Grass Family
Poaceae, subfamily Pooideae, tribe Bromeae
Grass Category
Invasive/Weed Grass
Variety / Cultivar
Wild type (no distinct cultivated varieties; highly adaptable weedy ecotypes exist)
Hardiness Zones
Thrives across USDA Hardiness Zones 3 through 9, highly resilient to extreme winter cold and summer heat due to its annual life cycle passing harsh seasons as a dormant seed.
About This Grass
An upright, slender annual grass that starts green in early spring, turning a distinctive purplish-green and eventually straw-colored or reddish-brown by early summer. Height ranges from 6 to 24 inches. Features drooping, densely clustered, one-sided panicle seed heads that become dry, sharp, and barbed at maturity.
Blade Characteristics
Blades are fine to medium (2-3 mm wide), flat, soft, and covered in fine, soft hairs (pubescent) on both surfaces. Vernation is rolled in the bud. Ligule is membranous and lacerated/jagged. Auricles are absent.
Root System
Shallow, fibrous root system that develops rapidly in early spring, allowing it to deplete soil moisture before native perennial grasses can establish. Does not form a dense sod or thatch.
Growing Information
Origin Region
Native to Eurasia, the Mediterranean, and parts of Europe; naturalized widely across North America and other temperate regions
Growth Habit
Bunch-type (clump-forming) annual, spreading aggressively by abundant seed production rather than rhizomes or stolons
Sunlight & Water Needs
Requires full sun and thrives in arid to semi-arid environments. Extremely drought-tolerant as an annual because it completes its life cycle before summer drought hits. Prefers well-drained, disturbed soils.
Mowing & Maintenance
Not utilized as a turfgrass; high maintenance level in terms of eradication. Hand-pulling, controlled burns, or pre-emergent herbicides are used for management.
Special Characteristics
High invasiveness, rapid seed germination in autumn or early spring, sharp awns at maturity that can injure the eyes, mouth, and skin of grazing livestock and pets, and increases wildfire frequency by creating heavy fine dry fuel.
Ecological Information
Considered a severe invasive weed in North America, particularly in the Great Basin and western rangelands. Outcompetes native vegetation, provides low-quality temporary forage only when very young, and alters natural fire regimes.