Preventing the Spread of Japanese Knotweed

 

Japanese knotweed is an aggressive invasive plant species that is becoming more widespread in the state of New Hampshire and the northeast. Because it can be spread vegetatively, the probability of moving Japanese knotweed during routine maintenance and in fill material associated with construction activities is increasing across the state, leaving municipalities and landowners with the costs associated with remediation of this destructive weed. Because of this, it is worthwhile to consider how to address Japanese knotweed movement prior to maintenance activities and during the planning phase of construction projects, rather than mitigating the damage post-construction.

These Best Management Practices (BMPs) will help you to understand:

  • Risks associated with Japanese knotweed;
  • How Japanese knotweed is moved, both naturally and as a part of maintenance and construction activities;
  • Identify some basic critical control points to reduce the movement of Japanese knotweed;
  • Provide some Integrated Pest Management (IPM) based control methods for Japanese knotweed.

Prepared by Douglas Cygan. Published by the New Hampshire Department of Agriculture, Markets and Food, 2018.