Found Japanese Knotweed? What the Rules Say

Your legal duties

• You must stop Japanese knotweed on your land from spreading off your property.
• You do not legally have to remove it from your land unless it is causing a nuisance, but you can be prosecuted for causing it to spread into the wild.
• You must not plant invasive non-native plants in the wild, or cause them to grow there. GOV.UK notes this can include moving contaminated soil or plant cuttings.

Treatment takes time

GOV.UK says spraying or injecting the stems with approved herbicides can be an effective treatment, but you will have to respray, and it usually takes at least 3 years to treat Japanese knotweed. The rhizome (underground stem) can lie dormant in the soil for many years and will regrow if disturbed or if the soil is moved.

GOV.UK also advises not to treat knotweed yourself unless you have the appropriate skills and experience.

Rules for spraying

When chemicals are used, GOV.UK says you may need to:

• make sure anyone spraying holds a certificate of competence for herbicide use, or works under the direct supervision of a certificate holder
• carry out a COSHH (Control of Substances Hazardous to Health) assessment
• get permission from Natural England if the area is protected, such as a site of special scientific interest
• get agreement from the Environment Agency if the plants are near water

Waste and disposal

• Soil or plant material contaminated with Japanese knotweed may be classified as controlled waste.
• To dispose of it off site you must use a registered waste carrier and take it to an authorised landfill or other suitable site.
• Most invasive non-native plants cannot be composted because they survive the process. GOV.UK does allow dead brown knotweed canes to be composted on site if they are cut (not pulled) at least 10cm above the crown.
• Burying on site has strict conditions, including notifying the Environment Agency at least one month beforehand.

How we can help

We provide herbicide treatment of Japanese knotweed and other invasive weeds. Our operator holds PA1, PA2, PA4, PA6 and PA6AW certificates of competence, including PA6AW for application in or near water, and we are a registered waste carrier.