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DescriptionAmur corktree is native to eastern Asia including Northern China (Manchuria, Ussuri, Amur), Korea, and Japan and was introduced into the United States in 1856 for ornamental purposes. To date, it has been reported to be invasive in scattered locations in Illinois, Maryland, Massachusetts, New York, Pennsylvania and Virginia. It prefers full sun and rich soils. Once established, it can form patches that displace native plants. It spreads by seed which is produced in abundance. Amur corktree can reach 35-45 ft. at maturity. The distinctive bark is a light golden brown on younger trees and gray-brown, ridged, and furrowed on mature trees. Bark of both young and old trees is slightly spongy or corky to the touch and has a distinctive bright neon yellow layer of inner bark that can be revealed with a quick scrape of a pocket-knife. The leaves are 10-15 in. long, opposite, pinnately compound with 5-11 (up to 13) entire leaflets that are dark green, turning bright yellow in the fall. When crushed, the leaves have a distinctive citrusy smell sometimes likened to a disinfectant or skunk odor. Male and female plants are separate (dioecious) and each bears hanging panicles of yellowish-green flowers from May through June. From mid-June to mid-July, female trees produce abundant clusters of fruits (technically drupes) which are ¼-½ in. diameter. The fruits bright are green, turning black in late summer to fall, and may remain on the tree until winter. It is a plant to watch and should be controlled as necessary.