Phellodendron amurense

The Amur cork tree is small to a medium-sized deciduous tree that has a rounded, broad spreading crown with horizontal branching, and grows to a height of 30 to 45 feet tall and 40 to 50 feet wide. It has a distinctive thick, corky, and spongy bark and a shorter trunk. The leaves are compound, oddly pinnate, dark green, and opposite. Each leaf has 5 to 11 leaflets. This species has separate male and female trees. The flowers are yellowish-green panicles that bloom in May or June. The female flowers produce small drupes that mature in the fall and persist through the winter months. When the foliage is bruised, it has an unpleasant odor or turpentine scent. 

This tree is native to Northern China, Korea, and Japan. It is typically found between Siberia and China in the moist soils along the Amur River. The Amur cork tree was introduced in the United States in 1856. It was favored as a shade tree, street tree, and tree for the home landscape. Currently, it has lost popularity due to its tendency to be invasive and weedy, particularly in the Northeastern United States. It is reported as invasive in Illinois, New York, Pennsylvania, and Virginia.  It is also listed as a noxious weed in the Midwest United States. 

The genus name, Phellodendron, is derived from two Greek words. Phellos means cork, and dendron means tree or treelike structure. The specific epithet, amurense, refers to its native habitat along the Amur River. The common name, cork tree, references the similarity of the bark of this tree with the unrelated oak tree, Quercus suber.

The Amur cork tree prefers full sun, and moist, well-drained soils. It is adaptable to different soil types. It is drought-tolerant once established and air-pollution-tolerant. The shallow wide-spreading root system makes this tree easy to transplant. The female tree produces thousands of seeds, and the tree can reproduce by seed or by re-sprouting. 

Amur cork tree has demonstrated invasive characteristics. It tends to invade and replace native hardwood trees. The female tree has the potential to become invasive; therefore, it may be best to consider planting the male non-fruit-producing tree or cultivar.

This tree was favored for use in the landscape as a shade tree or use in parks, golf courses, highway medians, or large parking lots. Its bark adds winter interest to the landscape. Due to its invasiveness and weedy potential, consider adding a native plant to your landscape.

Seasons of Interest:

Bark: Winter   Bloom:  Spring     Foliage: Spring, Summer, and Fall     Fruits:  Fall

Quick ID Hints:

• deciduous tree, short trunk, broad spreading crown, 35 to 40 feet tall and 40 to 50 feet wide
• bark is thick, corky, and spongy
• foliage is yellowish-green to green, compound, oddly pinnate, 5 to 11 leaflets
• flowers are yellowish-green panicles in the spring
• fruits are small black drupes in the fall

Insects, Diseases, and Other Plant Problems: This tree has no serious insect or disease problems.

VIDEO created by Andy Pulte for “Landscape Plant Identification, Taxonomy, and Morphology” a plant identification course offered by the Department of Plant Sciences, University of Tennessee.