What’s the problem with Japanese Knotweed?

Japanese Knotweed is a highly invasive plant which will spread quickly all over your garden or site, it can grow 10cm per day. Japanese Knotweed, if allowed to spread, will crowd out all other plant species and seriously reduce bio-diversity wherever it grows. It can regenerate from rhizome (root) as small as 0.4g therefore there is a massive risk of spreading the plant if you dig around it while doing gardening or building work. Knotweed can cause structural damage to your home and garden walls and destroy paths and drives. It can find cracks and weaknesses in buildings, forcing its way through foundations, concrete and brickwork. It will grow through tarmac drives and paths.

People have been refused mortgages on properties with Knotweed.

Can’t I just dig it up?

You can try! However, it is a really tough plant that only spreads through it’s roots which are known as rhizomes. The rhizome, according to The Environment Agency Guidelines, can grow to a depth of 3m or more and up to 7m away from the plant. The tiniest piece of rhizomes left in the ground will grow into a new plant. Continuous cutting and digging over many years may weaken it’s growth and control it’s spread but is highly unlikely to eradicate it.

Japanese Knotweed and the Law

Japanese Knotweed can also cause legal problems. It is against the law to allow it to spread into neighbouring property or to cause it to grow in the wild. The plant and its roots are classed as Controlled Waste and can only be moved by a Licensed Waste Carrier. You are not allowed to move it from your property yourself. It is not allowed in Local Authority Waste Disposal Sites or Council Green Bin schemes. It is regulated by several pieces of legislation, including:

The Wildlife and Countryside Act (as amended) 1981

The Environmental Protection Act 1990

The Environmental Protection (Duty of Care) Regulations 1991

You can take a civil case and seek damages if someone allows Japanese

Knotweed to spread onto your property. This means that a landowner with a Japanese Knotweed infestation has a duty of care to be proactive in the control and eradication of it. Planning permission will also generally be refused without an eradication programme in place for the infestation.

All parts of the plant and any soil contaminated with the rhizome are classified as controlled waste and are required, legally, to be removed and disposed of by a licensed waste control operator.

Claims may comprise of a private claim in nuisance or a private prosecution under The 1981 or 1990 Acts. The main objective is to take legal action quickly to ensure that remedial action is taken to ensure that the incidence of Knotweed does not hinder a potential development plot or damage neighbouring land.