Large Crabgrass
Digitaria sanguinalis · Warm-season, Annual, C4
Grass Family
Poaceae, subfamily Panicoideae
Grass Category
Invasive/Weed Grass
Variety / Cultivar
Wild type (no specific cultivated varieties)
Hardiness Zones
USDA Hardiness Zones 2-10 (as a summer annual, killed by the first hard frost).
About This Grass
An aggressive, coarse summer annual weed with a sprawling, sprawling-to-ascending growth habit. Can reach heights of 6 to 24 inches if left unmowed. Bright to yellowish-green color, turning purplish or reddish-brown late in the season. Forms finger-like racemes at the tips of flowering stems.
Blade Characteristics
Blades are medium to coarse in width (4-10 mm), flat, sparsely hairy on both surfaces, with pointed tips. Vernation is rolled in the bud. Ligule is membranous and jagged. Auricles are absent.
Root System
Shallow, fibrous root system with stolons that root at the nodes when touching moist soil. Establishes rapidly from seed in spring, forms a loose sod, and has moderate drought tolerance via summer dormancy.
Growing Information
Origin Region
Native to Europe and temperate Asia; now naturalized worldwide in temperate and tropical regions.
Growth Habit
Stoloniferous and prostrate, rooting at the lower nodes, spreading outward from a central clump to form dense, mat-like patches.
Sunlight & Water Needs
Requires full sun and open areas; very poor shade tolerance. Moderate to high water needs for germination, but highly resilient during dry summer spells by entering dormancy. Thrives in compacted, poor, alkaline to neutral soils.
Mowing & Maintenance
Mow low (1.5 to 2.5 inches) to suppress seed head formation. High maintenance as a weed requiring pre-emergent and post-emergent herbicides, hand-pulling, and core aeration to alleviate soil compaction.
Special Characteristics
Extremely high seed production per plant, excellent tolerance to poor soil and compaction, highly invasive in thin turfgrass lawns, rapid recovery from low mowing.
Ecological Information
Introduced species and noxious lawn weed. Provides minimal wildlife food value (seeds eaten by some birds), but its aggressive nature often crowds out desirable turfgrasses. Controlled best through dense turf competition and pre-emergent herbicides.