EPPO Global Database

EPPO Reporting Service no. 09 - 2005 Num. article: 2005/135

Cut-and-inject herbicide against Reynoutria japonica in United Kingdom

In 1999, the National Trust of UK commissioned a three-year research project to look at alternative methods of herbicide control to manage Reynoutria japonica (Polygonaceae - EPPO List of invasive alien plants). Research studies looked at optimum concentrations, timing and application techniques. Effects on surrounding ground flora, trees and shrubs were also investigated. Glyphosate was found to be the most effective herbicide in most situations and authorized to be used near watercourses. Its efficacy varied, depending on soil depth and how well established the plant is. All R. japonica plants must be treated on site to prevent reinfestation. It is important to revisit the site annually and tackle any regrowth. Where infestations straddle boundaries, it is important to work with neighbours.


Ford S (2005) Cut-and-inject herbicide of Japanese Knotweed. British Wildlife, October, p 20.