Large Crabgrass
Digitaria sanguinalis · Warm-season, Annual, C4
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Invasive/Weed Grass
Variety / Cultivar
Common wild large crabgrass (D. sanguinalis)
Hardiness Zones
Grows as an annual in USDA Zones 2-11; dies off completely with the first hard frost but leaves behind thousands of seeds.
About This Grass
A coarse-textured, pale green annual weed that emerges in spring. It grows in a rosette pattern, branching outwards. If unmowed, it can reach 2 feet in height. Seed heads are digital-like (finger-like) spikes emerging late summer.
Blade Characteristics
Coarse (typically >5mm wide), flat, with a prominent midvein. Blades are relatively short, hairy on both surfaces (hairy sheaths are a defining trait), light green to lime green. Vernation is rolled; ligule is large, membranous, and jagged; auricles are absent.
Root System
Shallow, fibrous root system; establishes extremely fast in disturbed or thin turf areas. Nodes touching the soil quickly strike roots, increasing its footprint.
Growing Information
Origin Region
Native to Europe and Asia; highly invasive and naturalized throughout North America and worldwide.
Growth Habit
Prostrate, spreading, and decumbent; produces roots at the lower stem nodes (stoloniferous-like behavior) forming dense mats.
Sunlight & Water Needs
Full sun preferred; thrives in hot, dry conditions where lawn grasses thin out. Very drought tolerant but responds aggressively to frequent watering.
Mowing & Maintenance
High maintenance weed; thrives at low mowing heights by spreading horizontally. Managed by pre-emergent herbicides in early spring and maintaining lawn height at 3-4 inches to shade out seedlings.
Special Characteristics
Highly competitive, opportunistic grower; allelopathic tendencies (inhibits growth of neighboring plants); extremely high seed production (up to 150,000 seeds per plant).
Ecological Information
Introduced/Invasive status in lawns; provides food for some birds (seeds), but generally considered a nuisance that out-competes native or desirable turf species.