Know your Japanese Knotweed or Pay the Price
Japanese Knotweed is classified as one of the top 100 worst invasive species worldwide, and it can cause serious damage to houses and buildings. Knotweed’s capacity to grow from fragments has important implications for control, with movement of knotweed-infested soil being one of the main reasons for its rapid spread across Ireland.
The number-one rule when faced with an infestation is: do not disturb it until a plan of action is devised and implemented. Ignoring this rule may lead to infestations that are impossible to eradicate.
Infestations on neighbours’ property may also be problematic. Landowners are not legally obliged to remove knotweed from their land but, if the landowner causes it to spread across the boundary, then it may constitute ‘knowing dispersal’. Awareness raising with the neighbour and reaching an amicable agreement is the recommended way forward following up with legal advice on potential civil proceedings should the problem continue.
Action Plan
Don’t disturb infested area, particularly soil & other ground materials.
Do engage expert Environmental Consultants to:
- Conduct a site assessment to establish: 1) the severity of the infestation and 2) site variables which may influence options for treatment.
- Advise on the best approach to eradication given site variables. A phased approach using a combination of methods can be most effective. Be fully aware of the consequences of different methods. Japanese knotweed is rarely eradicated in one attempt and this must be factored into works schedules and budgets.
- Prepare an invasive species management plan which details the agreed eradication programme, the methods to be used, the rationale for the choice of method, a schedule with milestones, a plan for contingency, and an assessment of the risk of re-colonisation of the site from other infestations in the locality. This is an important document to provide evidence of good practice in the event of future litigation.
Consequence – Legal, Financial, Time