Crabgrass (Large/Hairy Crabgrass)
Digitaria sanguinalis · Warm-season, Summer Annual, C4 specialized
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Invasive/Weed Grass
Variety / Cultivar
Wild type (weedy)
Hardiness Zones
USDA Zones 2-11; dies with the first hard frost but leaves behind thousands of seeds that survive extreme cold to germinate the following spring.
About This Grass
A coarse, light-green annual weed that emerges in spring. It features a sprawling, star-like growth pattern that smothers desired turf. Seed heads are digital (finger-like) spikes appearing in mid-to-late summer.
Blade Characteristics
Coarse width (>4mm), flat blades with pointed tips. Color is typically pale to lime green. Features a prominent midvein, rolled vernation, a tall membranous ligule, and distinct hairs at the base and on the sheaths (sheaths often reddish-purple).
Root System
Shallow, fibrous root system that expands rapidly; opportunistic rooting occurs wherever stem nodes touch moist soil. Lacks true rhizomes/stolons but behaves like a stoloniferous plant via rooting decumbent stems.
Growing Information
Origin Region
Native to Europe and Western Asia; naturalized globally in temperate and tropical regions with high performance in disturbed soils.
Growth Habit
Prostrate, spreading bunch-type that roots at the nodes (decumbent); creates dense, radiating circular mats.
Sunlight & Water Needs
Full sun (intolerant of shade); high drought tolerance once established but thrives in frequently watered or over-irrigated lawns. Prefers compacted, nutrient-rich soils.
Mowing & Maintenance
Maintenance involves prevention rather than cultivation. Hand-pulling or post-emergent herbicides are used. Mowing low (under 2 inches) can actually encourage its spreading habit.
Special Characteristics
Extremely high traffic tolerance; prolific seed producer (up to 150,000 seeds per plant); allelopathic tendencies that inhibit the growth of surrounding desired grasses.
Ecological Information
Invasive status in lawns; opportunistic colonizer of bare soil; provides some food for small birds and livestock but generally considered a nuisance that reduces biodiversity in local turf ecosystems.