|Natural Biodiversity uses a scientific approach in its efforts to control Japanese knotweed, kudzu, and other invasive non-native plants.
An Integrated Pest Management approach employs best-available practices that emphasize prevention. Resulting data are studied and approaches updated accordingly through Adaptive Management.
Increasingly, Natural Biodiversity is practicing prevention and rapid response by attempting to identify new colonies of invasive species and to eradicate them before they become a problem.
Currently, three methods are used at knotweed control sites:
1. Biannual herbicide application. Each spring and fall, herbicides are applied selectively on invasive plants (to prevent over-spraying and harm to other species).
|2. Summer cutting/fall herbicide application. Invasive plants are cut by the end of July to allow for limited regrowth, which is then sprayed after Labor Day but before the first killing frost.
3. One-time rhizome disturbance/herbicide application. Also known as “excavation,” this process breaks up the rhizomes in the fall usually via a backhoe turning over the soil to expose more plant surface area, which is then sprayed each spring and fall.
Our studies have shown that summer cutting and fall spraying results in the greatest yearly reduction in plant density and costs and cuts herbicide use in half.
It takes six people working six hours to control one acre of Japanese knotweed. But that volunteer effort can be quantified and used as required matching funds for grants.