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Japanese Knotweed

What is Japanese knotweed?

Japanese knotweed is one of a number of invasive plants that can cause problems to your property:

● It’s a large clump-forming plant, which grows up to 3m tall, with light green shield-shaped leaves with a flattened base, approximately 10-15cm long.
● The stem is hollow, bamboo-like, light green speckled with pink-red.
● There are only female plants in Britain, so no viable seeds are produced.
● The flowers are tiny and clustered together in creamy-white sprays, present from August to October.
● It produces thick and extensive roots called rhizomes, orangey-yellow inside, and spreads by fragments of rhizome. A piece the size of your thumbnail is sufficient. Fragments of rhizome get picked up in soil and on equipment.
● Over the winter the plant dies back leaving tall brown canes but as a perennial plant its top growth is renewed each year from the rhizomes which can spread relentlessly.
If you believe you have Japanese Knotweed please log on to http://www.property-care.org/homeowners/invasive-weed-control/ for further information.