A Knotty Nuisance: Japanese Knotweed For Developers

The legal implications of developing land adjacent to this highly invasive plant may be more extensive than you thought.

Japanese knotweed, a non-native plant introduced to the UK in the 19th century, is very difficult to eradicate and can grow up to 10cm a day in the summer months. The plant's underground rhizome (root) system is extensive and can lay dormant for long periods, meaning that cutting the plant down or digging up the roots is not an effective method of treatment.

The public perception of the problems caused by knotweed over the last decade has developed into a stigma for properties with, or even near, untreated knotweed. While it rarely causes structural damage, the time and expense of treatment means that knotweed is offputting to prospective purchasers and can reduce property values by 5%-10%.