Japanese Knotweed

Japanese Knotweed was introduced into Britain early in the 19th century as an ornamental garden plant and is becoming increasingly widespread in the West of Scotland.

Knotweed Summer View
Knotweed - Summer View

It is an upright, shrublike herbaceous perennial that can grow to over 2 metres in height, with an extensive system of underground rhizomes that may reach a depth of 2 metres and extend to 7 metres from the parent plant.

Extreme care should be taken to ensure that areas of knotweed are not cut, flailed or strimmed unless the work is being undertaken as part of an agreed control operation.  Where an area of knotweed is identified, no mechanical contact should be made with the plant, as research has shown that knotweed can be spread by the transfer of the smallest part of cut material.

Please Note: Whilst it is not an offence to simply have Japanese Knotweed growing on your land, the Wildlife and Natural Environment (Scotland) Act 2011 which came into force in July 2012 (superseding the Wildlife and Countryside Act 1981) states that it is an offence to spread intentionally or unintentionally Japanese Knotweed (or other non-native invasive species).  It puts the management of Japanese Knotweed in the hands of the landowner.  Therefore, Inverclyde Council has no remit in relation to Japanese Knotweed unless it is growing on Council land.

Where Japanese Knotweed is found growing on Council land, our policy is to eradicate it by repeated application of a suitable herbicide in areas where the plant could encroach onto someone else's land or in high profile public areas.  If you find Japanese Knotweed growing on Council land adjacent to your property, please report it to to our Customer Service Centre.

For guidance on how to deal with Japanese Knotweed on your own land, follow the External link to the Scottish Environment Protection Agency website.