Large Crabgrass (Smooth Crabgrass mix)
Digitaria sanguinalis · Warm-season, Annual, C4
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Invasive/Weed Grass
Variety / Cultivar
Common Wild Type (Non-cultivated weed)
Hardiness Zones
USDA Zones 3-11 (as an annual). It germinates when soil temperatures reach 55°F (13°C) for several days and is killed by the first hard frost.
About This Grass
A coarse, light-green summer annual weed that grows rapidly in heat. In a lawn setting, it appears as a wide-bladed, sprawling clump that disrupts the uniformity of fine-textured turf. If unmowed, it can reach 2 feet in height, producing finger-like spikelets as seed heads.
Blade Characteristics
Coarse blade width (>4mm), tapering to a sharp point. Blades are light green to yellowish-green with a prominent mid-vein. Vernation is rolled in the bud. Ligule is tall and membranous; auricles are absent. The sheath and blades are often covered in long, stiff hairs (especially in D. sanguinalis).
Root System
Shallow, fibrous root system that establishes extremely fast in disturbed or thin soil. Does not form a permanent sod but creates dense mats that smother desired grasses.
Growing Information
Origin Region
Native to Europe and Asia; widely naturalized throughout North America in temperate and tropical regions.
Growth Habit
Prostrate, spreading habit; primarily bunch-type initially but develops decumbent stems that root at the nodes (stoloniferous-like behavior).
Sunlight & Water Needs
Thrives in Full Sun; requires at least 6 hours of direct light. Highly opportunistic with water, exhibiting high drought tolerance once established but thrives in moist, nitrogen-rich soils.
Mowing & Maintenance
Not maintained; usually controlled via pre-emergent herbicides. It can survive mowing heights as low as 0.5 inches by sprawling horizontally. High maintenance level due to constant removal needs.
Special Characteristics
Extremely high wear tolerance; prolific seed producer (up to 150,000 seeds per plant); allelopathic tendencies that inhibit the growth of surrounding turfgrasses.
Ecological Information
Introduced/Invasive status in lawns. Seeds provide food for some songbirds (e.g., sparrows), but generally considered a nuisance that out-competes native or desirable forage and turf species.