Common Name: crabgrass, large
Species: Digitaria sanguinalis (L.) Scop.
Bayer Code: DIGSA

Large crabgrass (also called hairy crabgrass) is a common weed in turfgrass situations, and can germinate from March through early May in North Carolina when soil temperatures reach 53 to 58°F at a 4-inch depth. This weed is found in a variety of habitats. Germination of this weed is encouraged by the alternating dry and wet conditions at the soil surface in the spring. Stems have a prostrate growth habit and may root at the lower nodes. Large crabgrass is similar to smooth crabgrass. However, the leaf blade of smooth crabgrass is not as hairy, with a few hairs near the base of the blade. Leaf blade edges of smooth crabgrass are either not hairy or have sparse hairs.
large crabgrass plant
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large crabgrass seedhead
large crabgrass seedhead
large crabgrass seedhead
large crabgrass leaf blade width
Seedhead / Flower raceme2 - 9 spikelets arising from different points along the top of stems
Vernation Type rolledleaves rolled in the bud
Ligule Type membranous0.04 - 0.08 inches (1 - 2 mm) long, rounded to sharp pointed, toothed, often reddish
Growth Season / Life Cycle summer annual weed 
Auricle Type absent 
Leaf Blade Tip Shape sharp-pointedcovered with short hairs on both surfaces, sharply creased below, edges rough with scattered hairs
Leaf Blade Width broad, greater than 0.2 in0.2 - 0.6 inches (5 - 15 mm) wide
Stolon Presence present 
Rhizome Presence absent 
Collar Type  indistinct, mostly divided, hairy edges
Sheath Margin open 
Sheath Type flattenedsheath has long hairs; often with purple veins