University of Missouri Extension

IPM1007, Revised November 2009

Practical Weed Science for the Field Scout: Corn and Soybean

Crabgrass, smooth (Digitaria ischaemum)

Summer annual grass

Smooth crabgrass Smooth crabgrass
Smooth crabgrass

A summer annual grass with a prostrate or ascending growth habit, but unlike large crabgrass, with leaves and sheaths that do not have hairs and stems that do not root at the nodes. Leaf blades are 2 to 6 inches long, 2 to 7 mm wide, without hairs. Sheaths are essentially hairless but occasionally may have hairs in the collar region only. Ligules are 1 to 2 mm long and membranous. Seedlings or mature plants often have a reddish tint at the base. Seedheads are composed of 2 to 6 branches (spikes) at the top of stems, each about 2 inches long. Smooth crabgrass is often confused with broadleaf signalgrass and Texas panicum but does not have a hairy ligule like these other species.
 

IPM1007, revised November 2009

Wild thing
 

IPM1007 Practical Weed Science for the Field Scout: Corn and Soybean | University of Missouri Extension

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