Japanese knotweed, Polygonum cuspidatum (P. Seibold), might be discovered in yards, in ignored or former yard websites, and waste places. In some areas, it has escaped from growing to end up being an extremely aggressive, troublesome weed. This vigorous, handsome, bushy, sturdy perennial was developed as a screen and for the strong effect of its foliage and the clouds of whitish bloom in the late summer season. The plant is sometimes offered with the deceptive name “Mexican bamboo.” But It was not provided from Japan and is neither Mexican nor relevant to the bamboo. It belongs to the buckwheat family, which includes rhubarb, the decorative plants silver lace-vine and princes-feather, and such weeds as lady” s-thumb, smartweed, prostrate knotweed, curled dock, and sheep sorrel.
Japanese knotweed plants form globs and send long roots (underground stems) deep underground. New shoots grow from the seeds yearly and reach 3 to 9 feet high. Stems are round, smooth, frequently mottled reddish-purple, hollow between the nodes or joints, and may be branched or un-branched. The ocrea (sheath around the stem at each node) is membranous and soon breaks down. The stems and leaves return to the ground after the first hard frost.