The leaves are green, shield or heart-shaped, with a flat base and are up to 12cm long.
The stems are green with red or purple specks, hollow and similar to bamboo, and can grow up to 2- 3m tall, forming dense cane-like clumps.
The roots consist of rhizomes, which are yellow / orange when cut, but can spread to a depth of 3m and radius of 7m.
Clusters of creamy flowers appear on the tips of most stems from August to October but produce sterile seeds.
In the spring, Japanese Knotweed emerges from winter dormancy with new leaves initially being reddish in appearance with an arrow shaped tip up to 4cm long.
2-3 metre stems, which are hollow with nodes that resemble bamboo. The leaves will be green in colour appearing from zig-zag plant growth. In late summer the plant will start to produce white flowers.
Similar to late summer, approaching late autumn the leaves start to go yellow and start wilting, this is a sign of the plant starting to pull all the nutrients from above ground.
Japanese Knotweed canes will begin to die back and the plant will lose its leaves, leaving dried brittle canes.
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