Japanese knotweed
Why should a surveyor’s “possible knotweed” not be treated as a confirmed management category?
Because the 2022 categories apply when Japanese knotweed is identified. “Possible” means the surveyor is not sure, often because growth was dead, immature or similar to other plants. You need an identification before you report category A, B, C or D to a lender or a seller.
Last reviewed 24 October 2026. Written for buyers in England and Wales unless this answer says otherwise. No named surveyor has signed this page. It is general guidance, not a report on your house, and not legal advice.
What is the fuller explanation?
Several plants throw up bamboo-like canes. A surveyor who is not sure should say so and should not force a category the journal defines for identified knotweed. The journal still wants a specialist involved where knotweed is seen within the boundaries. Where it is only possible, the practical next step is a person who can identify it, in the growing season if necessary. That identification is what a category would then be based on.
Do not announce to a lender that the property is category A because a survey said “possible”. Equally, do not delete the sentence because you hope it is bindweed. GOV.UK’s rules apply once it is knotweed. Until then, the honest status is unconfirmed. Ask the surveyor what features they saw, and ask a specialist to confirm or rule the plant out.
What should you ask your surveyor?
- What did you see that made you say possible, and what did you not see?
- Are you assigning a management category, or waiting for identification?
- When would identification be reliable if the visit was out of season?
What are the typical next steps?
- Instruct an identification, not a herbicide contract, if the plant is only possible.
- Tell your solicitor the finding is unconfirmed so the seller is asked a precise question.
- Do not start excavation on a possibility.
Costs vary with the building and with who you instruct. Where this page does not cite a published figure, ask the surveyor, a relevant specialist, or your solicitor for a written quote. Do not treat a forum average as the price.
Also asked about this
Can bindweed be reported as category C?
No. The categories are for Japanese knotweed. A different plant should be named as a different plant, or left as unconfirmed.
Who pays for the identification?
That is a negotiation. The survey does not send the bill to the seller. Ask your solicitor what the contract allows.