This vine was introduced from Japan to the U.S. in 1876 as an ornamental plant, and was later promoted as a natural way to mitigate soil erosion. In fact, farmers in the southern U.S. were paid to plant kudzu on over one million acres. Not surprisingly, kudzu is established throughout the southeastern U.S., and is moving to the Midwest and Northeast. Kudzu spreads primarily by runners (vegetative shoots) that root at the nodes; spread by seed is rare. Kudzu rapidly grows over anything in its path, and commonly covers entire mature trees in a blanket of vines. This plant can suppress native plant growth and prevent other plants from growing across large areas where it is established.
This many-branched vine can climb and cover tall trees, poles and even buildings. It also forms extensive mats over fields and low vegetation. Kudzu can grow a foot a day. Younger stems are yellow-green and covered with golden/bronze bristly hairs, while older stems are woody, hairless and gray/brown in color. First year vines can reach ½ inch in diameter and older stems can be 4 inches thick. Pods are hairy and contain 3-10 seeds which can remain viable for years. Each leaf, made of 3 leaflets, can be up to 8 inches long. Leaves are large, dark green, deciduous and borne alternately along the stem. The leaf stalk and undersides of leaves are hairy. Each leaflet has toothless edges and often is notched or lobed. The middle leaflet is on a short stalk and is usually 3-lobed; the outer leaflets are 1-2 lobed. Pea-like flowers appear on spikes (up to 8 inches long) in leaf axils, blooming from base to tip. Flowers are reddish-purple, very fragrant and appear in mid to late summer.
Management is difficult, but can be accomplished by removal of the root crown (a knobby mass of tissue at or just under the soil surface), repeated mowing (this depletes the plant of nutrients), or herbicides. Often, multiple methods are required to effectively manage kudzu. Biological control methods are being tested, and some (including a beetle and fungal spray) do show promise as potential management options.
What Can You Do?
Forest Health Forester