Japanese Knotweed Excavation
On large construction sites where work is in progress, the presence of Japanese knotweed can mean costly delays to the building process. However where possible, Japanese knotweed can be relocated to a quarantined area of the site for treatment later, allowing work to progress as normal on the rest of the site. The Japanese knotweed infestation can be treated with a chemical application at a later, more convenient time.
On-site burial
Japanese knotweed and contaminated soil can also be buried on site inside a heat sealed plastic membrane. This is ideal where no construction work has begun and the site can be fully excavated to make a hole deep enough to contain the knotweed.
The burial site must not be disturbed after excavation and re-burial and the location should be clearly marked on all site plans. The Environment Agency need to be advised that the burial of Japanese knotweed is taking place and all plans must be approved with them. It is very important that every last bit of Japanese knotweed is removed as a piece the size of your finger nail can regrow and create a new infestation.
Excavate and off site removal
This is the last resort and most expensive method but sometimes it just has to be done, especially for those sites where time is a constraint and there is no area on site to manage the waste. All waste will be removed and taken to a licensed landfill site.
This method of direct injection of herbicide is highly effective as it is absorbed throughout the rhizome and deep into the plant’s root system, helping to completely eradicate the troublesome plant.
Stem injection is a popular technique to use in environmentally sensitive areas such as close to water. This process minimises any risk to the water and environment surrounding the plant.
Our herbicide treatment programme consists of four applications, this can vary depending upon the plant’s uptake of the herbicide. We use SEPA & DEFRA approved herbicides applied at suitable times during the knotweed growing season (usually April to November).
Ideally preparation work is undertaken in the winter to cut, mulch & remove the dead canes and any items that might impede the new shoots in spring.