Japanese Knotweed: Legal Responsibilities and Control Strategies

Legal Framework in the UK

Japanese knotweed (Fallopia japonica) is listed under Schedule 9, Section 14 of the Wildlife and Countryside Act 1981, making it an offence to plant or cause it to grow in the wild. However, having it on your land isn't illegal, nor is there a specific law against allowing it to spread—though it may constitute a nuisance. Under the Environmental Protection Act 1990, knotweed is classified as "controlled waste." Soil containing rhizomes must be disposed of at a licensed facility, buried at least 5 meters deep at landfill sites.

Herbicide Treatment

For undisturbed areas, a multi-year herbicide strategy can eradicate knotweed. Spray annually until no regrowth occurs for at least two years. Near watercourses, Environment Agency permission (form WQM1) is required, and only non-persistent herbicides like glyphosate may be used. Away from water, more persistent herbicides like picloram (Tordon 22k) are an option.

Excavation

Excavation provides immediate removal but is costlier than herbicide treatment. It's suitable when knotweed hinders construction or obstructs waterways. All excavated material must be handled as controlled waste.