Large Crabgrass
Digitaria sanguinalis · Warm-season, annual, C4 grass
Grass Family
Poaceae, subfamily Panicoideae
Grass Category
Invasive/Weed Grass
Variety / Cultivar
Wild type, no specific cultivars for common turf weed
Hardiness Zones
USDA Hardiness Zones 3-10; thrives in warm summer conditions. Dies completely with the first hard autumn frost.
About This Grass
An annual grassy weed with a sprawling, semi-erect growth habit. Can reach 1-2 feet tall if unmowed, but frequently sprawls horizontally close to the ground. Light green to grayish-green color. Produces distinctive finger-like (digitate) racemes at the top of stems in summer and autumn.
Blade Characteristics
Medium to coarse width (4-10 mm), flat, pointed tip, light green to blue-green color. Rolled in the bud (vernation). Membranous ligule, lacks auricles. Blades and sheaths often sparsely hairy.
Root System
Shallow, fibrous root system with a strong tendency to root at the lower nodes where stems touch the soil. Fast establishment from seed in spring. Does not form a desirable dense turf sod.
Growing Information
Origin Region
Native to Europe and temperate Asia; now globally distributed in temperate and tropical regions
Growth Habit
Stoloniferous and spreading; roots at the lower nodes, forming a loose, sprawling mat
Sunlight & Water Needs
Requires full sun and does not tolerate dense shade. Moderate water needs, highly drought-tolerant once established due to efficient C4 photosynthetic pathway. Thrives in warm, dry soils.
Mowing & Maintenance
High maintenance weed in lawns; survives low mowing by spreading horizontally. Needs frequent mowing to remove seed heads. Hand pulling or selective/non-selective herbicides required for control.
Special Characteristics
Exceptional heat tolerance, high competitive ability in thin lawns, poor wear tolerance compared to dense turfgrasses, highly invasive in disturbed soils and thin turf.
Ecological Information
Introduced species acting as a troublesome agricultural and turf weed. Provides minor food source for some granivorous birds. Helps cover bare soil to prevent erosion, but generally outcompetes desired turf grasses.