Japanese Stiltgrass Control

by Rebecca Crow


japanese stiltgrass



On a recent residential site visit I was asked to advise on how to eradicate a very large patch of Japanese stiltgrass (Microstegium vimineum). This invasive plant hails from Asia and is now found in most of Eastern America. Its range extends to Texas, and its seeds can travel on the tires of construction trucks, cars, hiker’s boots and on the hair of animals. A tough annual plant, stiltgrass gets taller than other plants. When it dies, it forms a mat that smothers them. Yikes!

One solution suggested by Dr. Doug Tallamy, famed professor and founder of the native plant movement, is to plant goldenrod to thwart the expansion of stiltgrass. Solidago Canadensis, an aggressive native, will outgrow and crowd out stiltgrass, says Dr. Tallamy. See the YouTube video listed below.

After a deep dive into the topic of stiltgrass, I found these control methods:

1) In August, you can use a string trimmer. Because this is done in the late summer, the plant doesn’t have the energy to rebound or produce seeds for the Fall. Some sources recommend using a propane torch to burn it down, but fire danger is often high in August. Always check with the local fire authorities first before doing any outdoor burning.

2) After August, you can smother it with black tarp for 6 weeks or put down a 4-inch layer of mulch.

3) Surprisingly, the chemical herbicide glyphosate (found in Round Up) doesn’t do the trick. See the attached link to page 22, table 5.7 in VA Cooperative Extension’s Pest Management Home Grounds and Animals, 2024 Pest Management Guide, for recommended herbicides for stiltgrass.

4) For small amounts, hand pulling will work as the roots are shallow. If it has formed seed heads, dispose of it in a plastic bag and not in your compost!

 Resources
https://www.pubs.ext.vt.edu/.../456/456-018/ENTO-567-E.pdf
https://www.nybg.org/.../tip-of-the-week-removing.../
https://extension.psu.edu/controlling-japanese-stiltgrass...
https://extension.psu.edu/japanese-stiltgrass
https://www.youtube.com/watch?v=j7ligldtfc4




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