Large Crabgrass
Digitaria sanguinalis · Warm-season, Annual, C4
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Invasive/Weed Grass
Variety / Cultivar
Not applicable (wild-type/weed species)
Hardiness Zones
USDA Zones 2-11 (as an annual); dies back completely after the first hard frost but persists in the soil via a massive seed bank.
About This Grass
A coarse-textured, pale green to medium green annual grass that grows in a low-profile rosette. As it matures, it produces sprawling stems that root at nodes. It is highly competitive in bare soil or thin lawns. Seed heads are distinctive finger-like spikes (digitate) that appear in late summer.
Blade Characteristics
Coarse blades, 4-10mm wide; flat surface with a prominent white midvein; pointed tips; vernation is rolled; leaves and sheaths are typically hairy (pubescent). Ligule is membranous and tall; auricles are absent.
Root System
Shallow, fibrous root system; establishes very quickly from seed in disturbed soil; lack of deep roots makes it reliant on surface moisture, but rooting at nodes increases its stability and nutrient reach.
Growing Information
Origin Region
Native to Europe and Asia; widely naturalized across temperate and tropical regions of North America, South America, and Africa.
Growth Habit
Prostrate, decumbent, and bunch-type; spreads via rooting at the nodes (stoloniferous-like behavior in late season) to form wide mats.
Sunlight & Water Needs
Full Sun (highly light-dependent); high water needs for rapid growth but exceptionally drought-resistant once established due to its growth speed; prefers warm, moist conditions and well-drained soils with pH 5.5-7.5.
Mowing & Maintenance
Maintenance level is low as it is a weed; can survive mowing as low as 0.5 inches by adapting a prostrate growth habit. Control requires pre-emergent herbicides in early spring or manual pulling before seed set.
Special Characteristics
Extremely high wear tolerance; prolific seed producer (up to 150,000 seeds per plant); thrives in compacted soil and heat; allelopathic tendencies that can inhibit growth of surrounding desirable turf.
Ecological Information
Introduced/Invasive in turf settings; seeds provide food for small birds (finches, sparrows) and some small mammals; excellent at preventing immediate soil erosion on bare ground but generally considered a nuisance in managed landscapes.