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/invasive species)
Hardiness Zones
USDA Zones 2-11 (as an annual). It geminates when soil temperatures reach 55°F (13°C) and dies off with the first hard frost.
About This Grass
A coarse, prostrate annual weed with a pale to lime green color. It forms dense, low-growing clumps that branch outward. If unmown, it can reach 12-24 inches. The seed head is a finger-like raceme (3-13 spikes) appearing in late summer.
Blade Characteristics
Coarse blades, 5-10mm wide, flat with a prominent midvein. Tips are sharply pointed. The blades and sheaths are notably hairy (pubescent). Vernation is rolled in the bud. Ligule is membranous and tall; auricles are absent.
Root System
Shallow, fibrous root system that establishes extremely fast. It roots at the lower stem nodes (stolon-like behavior), enabling it to monopolize space and moisture rapidly. High thatch-like competition in turf.
Growing Information
Origin Region
Native to Europe and Asia; naturalized throughout North America and temperate/tropical regions worldwide.
Growth Habit
Stoloniferous and decumbent; stems spread horizontally across the ground, rooting at the nodes to form dense mats.
Sunlight & Water Needs
Full sun preferred; highly opportunistic in thin turf. Moderate to high water needs for rapid growth but highly drought-tolerant once established. Thrives in compacted, disturbed soils.
Mowing & Maintenance
Maintenance is usually centered on eradication. It can survive mowing heights as low as 0.5 inches by growing prostrate. High maintenance is required to prevent it from outcompeting desirable turf; requires pre-emergent herbicide in early spring.
Special Characteristics
Extremely high wear tolerance and heat tolerance. Highly invasive in home lawns. Able to produce thousands of seeds per plant, which remain viable in the soil for years. Minimal disease issues.
Ecological Information
Introduced species; considered a noxious weed in managed landscapes. It provides minor forage value for birds and small mammals but is generally sought for removal to protect native plant diversity and turf health.