Japanese Knotweed Flashcards
How would you identify Knotweed through the seasons
Spring:
Green leaves with a flat base and zig zag formation along the stems
Summer:
Budding white flowers
Autumn:
Brown leaves
Winter:
Black bare canes
What are common defects caused by Knotweed
- Gardens destroyed
- Cracked underground drains in search for water
- Growth under patios leading to cracks
- Boundary and retaining walls
- Outbuildings
What other common types of invasive species are there
Giant Hogweed
What remediation works are there to treat Japanese Knotweed
Excavation of roots:
Involves the removal of rhizomes in order to prevent future growth
Burial/ encapsulation with membranes:
Involves a 5m barrier membrane which encapsulates the roots preventing growth
Chemical treatment:
Cost effective however will need multiple treatments and can be seen as temporary solution
What impact on lenders is there from Knotweed
Can be difficult to secure a loan and insurers may be unable to provide cover
How would you estimate the impact on value?
Seek specialist advice, there are knotweed websites that produce a rough figure of value
What would you do if knotweed spread over Neighbouring boundaries
Setup a managment plan for the agreement of treatment works
If neighbours dont agree to works you will have to setup a policy where new owners agree to follow a continued treatment programme
What guidance has RICS provided on Japanese Knotweed
Japanese Knotweed and Residential Property 1st Edition 2012
What is the new approach to Japanese Knotweed outlined in the draft guidance note
More of a focus on management of the knotweed. The process utilises a decision tree, with detailed accompanying notes as an integral part of the assessment. This will place the property in a management category
What is the seven meter rule?
A rule of thumb which states if knotweed is found 7 meters from the boundary line the chances of a mortgage being granted are low due to the risk
