Japanese Wisteria (Wisteria floribunda)

As suggested by the name, this plant originated in Japan and was introduced to North America in the 19th century. It is a deciduous woody vine that will climb upwards; vines are brown and older specimens can be 15 inches in diameter. Leaves are up to a foot long with many leaflets. Flowers are small, less than an inch, purple-blue and grow off long racemes that hang down up to 3 feet off the vines. The fruits are velvety pods about 6 inches long, and the seeds contained within are the way that these plants spread.

The problem Japanese Wisteria poses is death by girdling to trees, as the vine climbs upwards around them. Vigorous growth also can create dense thickets that will shade out understory growth. The best management of these vines is cutting and application to herbicides. This will hinder growth of the plant and may not need repeating, but due to spreading by seed, repeated, long term action may be needed.