Large Scale Herbicidal Programme Mitigates Risks On Land With Multiple Tenants Potclays Japanese knotweed - Herbicidal Treatment

Ebsford have been presented with one of their biggest challenges - a large industrial site of approximately nine acres has a widespread and very mature Japanese knotweed infestation covering approximately 12,000m², increasing in density to the west of the site, and beginning to encroach onto the gardens of the properties of an adjacent road. The infestation issue may also be exacerbated by the movement of vehicles, as parts of the infestation are included in plots of land used by other companies. Upon observation of the infestation, it was clear that it was highly mature; the density of canes indicates that many crowns are present in the ground, as well as the presence of weathered canes on the ground from previous growing seasons. Historical research also confirmed that the infestation has been in situ for at least thirty years. A multitude of factors could have introduced the species to the site, as multiple industries have been present over the years with many delivery movements taking place. With the many media conversations surrounding the species, the client was aware of their requirements as a responsible business owner, and mindfully considered the local community and of course the environment in tackling the infestation. Although it has been managed on site for a number of years, when it became clear that the infestation presented a risk of encroachment onto the adjacent road, Ebsford also allowed the client to follow the Wildlife and Countryside Act (1981) in not allowing the species to spread.

A Japanese knotweed infestation covering this sheer amount of square metres is a mammoth task, and the site itself presents some obstacles – particularly dense areas required clearance in order to make them accessible. It is paramount for control of the species that full foliar application to the entirety of the infestation is achieved, as this means that chemical will effectively be absorbed through the leaves and translocated to the species’ root system, where control is achieved over the course of the treatment programme. The site is also incredibly steep in some areas, making accessibility of parts of the infestation a health and safety risk; this issue as well as the density of parts of the infestation has been overcome through the utilisation of machinery such as a cherry picker – this allows Ebsford to elevate operatives in order to spray chemical to areas of the infestation difficult to access from ground level. A herbicidal treatment programme of five years is proscribed in order to achieve long-term control of the species.