Large Crabgrass
Digitaria sanguinalis · Warm-season annual, C4 grass
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Invasive/Weed Grass, occasionally Pasture/Forage Grass
Variety / Cultivar
Common wild type (though 'Red River' and 'Impact' exist for forage uses)
Hardiness Zones
USDA Zones 2-11; annual life cycle means it dies with the first hard frost but survives as prolific seed in the soil.
About This Grass
A coarse, prostrate annual grass that forms dense, low-growing mats. It has a light green to lime green color, transitioning to reddish-purple with frost. Seed heads are distinctively finger-like (digitate) spikes branching from the top of the stem.
Blade Characteristics
Coarse width (>4mm), flat shape, pointed tip, light green color. Vernation is rolled. Features prominent hairs on the leaf blades and especially the sheaths. Ligule is membranous, tall, and jagged; auricles are absent.
Root System
Shallow fibrous root system; stems frequently root at the nodes (joints) where they touch the soil, allowing for rapid lateral expansion and difficult removal.
Growing Information
Origin Region
Native to Europe and Asia; highly invasive and naturalized throughout North America
Growth Habit
Decumbent or prostrate spreading; stoloniferous-like (roots at lower stem nodes/joints)
Sunlight & Water Needs
Full sun preferred; thrives in hot, dry conditions but grows aggressively with frequent summer irrigation. Very high drought tolerance once established.
Mowing & Maintenance
Low maintenance (as a weed). It can survive extremely low mowing (under 1 inch) by growing horizontally. In lawns, it is controlled via pre-emergent herbicides in early spring and post-emergents in summer.
Special Characteristics
Extremely high wear tolerance and heat resistance. Can produce up to 150,000 seeds per plant. Highly competitive in thinning turf or bare soil.
Ecological Information
Introduced species; considered a noxious weed in turf but provides high-quality forage for livestock in pastures. Seeds provide food for songbirds and small mammals.