Japanese Knotweed

Japanese Knotweed is a strong growing, clump forming perennial noxious weed with tall dense annual stems.

Stem growth is renewed each year from strong deeply penetrating rhizomes. In the spring and summer months the bamboo like shoots can grow to over 2/3 metres tall. Leaves can grow up to 15 cm in length and the white flowers which are produced in the summer and early autumn can grow to approximately 15cm. During the winter months the stems die back to ground level. Due to its strong growth and ability to spread it can do a great deal of damage – taking over other plants and, more seriously, causing damage to roads, paths, walls, building foundations etc. It is best for Japanese Knotweed to be treated for eradication as soon as possible.

Spray Treatment

This type of treatment is by knapsack sprayer and is an efficient way to treat large clumps of noxious weeds including Japanese Knotweed. For mature, well established weeds regrowth will occur in following years, and it is therefore necessary to put into place a programme of visits at the appropriate time of year, to carry out repeat spraying. Treatment will be required until regrowth has finished.

Stem Injection

This method is usually used on small clumps of Japanese Knotweed. This treatment requires a high concentrate of chemic and involves a specialist herbicide injection tool. Using this the chemic is injected directly into the stem of the Japanese Knotweed.  This treatment will continue until regrowth has finished.