Controlling Invasive Japanese Stilt Grass
How to Ensure that You Make Room for Native Plants in Your Yard
Aug 25, 2009
One of those invasives is called "Japanese stilt grass" (Microstegium vimineum). This aggressive annual plant is spreading like wildfire on the East Coast from Florida to New York. And as it spreads, it is crowding out native plant materials in our forested areas.
Experts believe that Japanese stilt grass first arrived in the U.S. in packing crates for porcelain dishes in the early 1900s. The dehydrated grass was spilled on walkways and spread via seed to nearby natural areas. Resembling delicate, mini-bamboo plants, stilt grass seemed innocuous enough at first. But it soon became apparent that it is able to colonize quickly. It especially likes disturbed areas, such as those that are under construction, and it is particularly good at growing in floodplains, ditches, and forested wetlands.
An Ability to Spread Quickly
Unlike most grasses, Microstegium vimineum can survive in deep shade, allowing it to quickly take over woodland patches. Each plant, which can produce up to 1,000 seeds each, spreads via root extension. The seed can last up to three years in the soil, making eradication even harder. And it is spread by animals and people who walk through the grass without realizing that they've become transporters.
Once this grass establishes itself in the forestal areas near your home, it will move into homeowner's lawns before they even realize there is a problem. From there, stiltgrass begins to multiply rapidly and crowd out the orchardgrass, timothy or fescue grasses that are more desirable lawn grasses.
Because no native animal or insect species is known to be able to eat this grass, Japanese stilt grass creates vast carpets of inedible spaces. It crowds out native understory plants such as shadbush and Rhododendron canescens that are critical to the continued health of the nation's forests. Microstegium vimineum is part of a large and growing problem in the U.S. in which exotic plant materials are replacing our important, and fragile, native species.
Combatting the Problem
There are several ways to combat Japanese stilt grass. Because the plant is shallow-rooted, it is quite easy to just pull up whole sections of a colonized area by hand. It's important to pull the grass or cut it before it sets seedheads. Homeowners who live on acreage may need to turn to contact or systemic herbicides, such as glyphosate or those designed to eradicate annual grasses. But they should be aware of use restrictions for these chemicals in wetland or forestal areas.
