Large Crabgrass
Digitaria sanguinalis · Warm-season, Annual, C4
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Invasive/Weed Grass
Variety / Cultivar
Common Wild Type
Hardiness Zones
USDA Zones 2-11 (as an annual); dies with first hard frost; seeds remain viable in soil for many years.
About This Grass
A coarse, pale green, summer annual weed that forms dense prostrate mats. It grows aggressively in disturbed soils and thin lawns, with stems that can reach 3 feet if unmowed. Seed heads are digital-like spikes radiating from the stem top.
Blade Characteristics
Coarse width (5-10mm), flat shape, pointed tip, light green to yellow-green color, rolled in the bud (vernation). Blades are notably hairy on both surfaces with a tall, membranous ligule and no auricles.
Root System
Shallow, fibrous root system that spreads by rooting at lower stem nodes (nodes that touch the ground); lacks significant thatch but forms dense, hard-to-pull patches.
Growing Information
Origin Region
Europe and Asia; naturalized globally in temperate and tropical regions
Growth Habit
Prostrate, spreading decumbent growth; roots at the nodes (stoloniferous-like)
Sunlight & Water Needs
Full Sun (requires high light intensity); high water needs for rapid growth but highly drought-tolerant once established; prefers acidic to neutral soils.
Mowing & Maintenance
Mowing height: adaptable (thrives even at 0.5 inches); Maintenance: generally targeted for removal; requires pre-emergent herbicide in early spring to control.
Special Characteristics
Extremely high wear tolerance; prolific seed producer (up to 150,000 seeds per plant); allelopathic tendencies that can suppress neighboring plants.
Ecological Information
Introduced/Invasive; provides some food for ground-feeding birds but is generally considered a nuisance that outcompetes native grasses and desirable turf in managed landscapes.