Japanese knotweed on council owned land

Where would I find it living?

Found in riverbanks, waste grounds and roadside verges, beds and borders where it prevents native species from growing.

Image
Japanese knotwood close up

What are the impacts?

This invasive plant thrives on disturbance.

  • the smallest piece can grow and spread by natural means and human activity
  • it can soon overrun riverbanks, railway embankments, road verges, gardens and hedgerows
  • it is a threat to the survival of native plants, insects and animals
  • it exploits week areas in structures if left unchecked, causing damage to hard surfaces, block drains and worsen cracks in building infrastructure
  • it can sometimes grow from seed too, this means that if Japanese knotweed is growing in a neighbouring garden it could likely come into your garden, either by its spreading roots or by seed

What is the removal process of Japanese knotweed?

green leaves of Japanese knotwood under shade
 

Cutting and digging are not effective methods for controlling established Japanese knotweed and take many years to have any effect. Japanese knotweed is best controlled by the application of a suitable herbicide. Glyphosate-based herbicides are commonly used to treat Japanese knotweed.

Read our policy on treatment of Japanese knotweed

Does Japanese knotweed need continuous monitoring?

Yes, Japanese knotweed can remain dormant underground for several years, so consistent monitoring is crucial even after treatment. Regular inspections should be conducted to identify and promptly address any regrowth or new infestations.

How do you report a sighting of Japanese knotweed on council land?

Report Japanese knotweed found on council land