Stiltgrass (Microstegium vimineum) is a low growing annual grass. This species prefers forested floodplains but will grow in any light or moisture condition. This grass can grow up to 6 feet but is typically shorter. The leaves are 2 to 4 inches long and are only ½ inch wide. They have smooth edges and are evenly spaced around the stem. Flowers and seeds appear on a spikes on top of the stem. The grass turns a purple to brown color on top during fall.
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Environmental Effects
Seeing how this species produces 100 to 1,000 seeds per plant, it spreads quickly and can form dense patches. Seeds are dispersed by wildlife, humans, vehicles, and water flow. Deer often avoid browsing on stiltgrass which further allows the species to spread. As with other invasive species, stiltgrass can outcompete natives and reduce native diversity.
Treatments
There are multiple treatment options for stiltgrass. These include both chemical and non-chemical methods.
NON-CHEMICAL CONTROL METHODS
- Hand pulling: the best time to hand pull this species is at the end of the growing season but before the seeds are ripe. It is best to bag the plant material and dispose of it in a landfill. You should expect to continue hand pulling the same area for at least 7 years to reduce the seed bank and resprouting.
- Mowing: this method is most effective in late summer to early spring. You should mow the plants as close to the ground as possible. It is best to return to the site weekly until all mature plants are cut. This prevents the area from being reseeded. You should expect to repeat mowing for at least 7 years to effectively reduce the seed bank.
CHEMICAL CONTROL METHODS
- Foliar spraying: this may be the most time effective method if the patch is dense. You can either spray individual plants or spray the general area of infestation. However, this will kill all plants in the vicinity. Note: follow all safety precautions and wear the proper personal protective equipment when handling herbicide.