Weed Grass in Fort Washington, MD

Asked July 31, 2018, 10:03 AM EDT

What is this weed (pictures attached). This weed has been growing in the shaded portion of my lawn for several years. It grows during the summer and dies in the winter. It has a shallow root base and will grow more than 12 inches if I did not cut it with my lawn mower. What can I use to kill this weed, prevent it from coming back each year, and not kill my lawn grass?

Prince George's County Maryland lawns and turf weeds japanese stiltgrass

1 Response

This looks like Japanese stiltgrass, an invasive weed. Next spring apply a preemergent to prevent it from germinating. Apply prior to seed germination which begins, in early spring a couple of weeks before you would apply a crabgrass preventer. Apply a preemergent without nitrogen fertilizer. Look for the active ingredient: Prodiamine (Barricade) or other preemergents labeled for crabgrass control. Keep the area mowed to help prevent the stiltgrass from forming seeds. Stiltgrass likes shade and but will move into other areas of your lawn.
Please see the following information from our website:
http://extension.umd.edu/hgic/problems/japanese-stiltgrass

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