Kentucky Coffee Tree
Growing in Eastern and Central North America from New York and Ontario, West to Minnesota and South to Kansas, Tennessee and Oklahoma, the Kentucky coffee tree (Gymnocladus dioicus) is a moderately large canopy tree belonging to the legume family. It is known by several other names, such as American coffee berry, Kentucky mahogany, nicker treet, or stump tree.
The Kentucky coffee tree was pitted against the Tulip Poplar for the distinction of being named Kentucky’s state tree. It eventually lost to the Tulip Poplar (also called Yellow Poplar or Tulip Tree) in 1994 but still retained the title of “unofficial Kentucky state tree.”
The Kentucky coffee tree is one of the only two remaining species of Gymnocladus still in existence. Its closest relative is in china. Gymnocladus means “naked branches,” which the Kentucky coffee tree has six months out of twelve.
The Kentucky coffee tree could reach heights of up to 60 to 100 feet, with its 1-2 feet diameter trunk dividing into several large branches. Its leaves are ovalish and about 2-4 inches long. The largest Kentucky coffee tree on record is found in Morgan County, Kentucky, at a height of 78 feet tall and over 17 ½ feet in diameter. Usually, a Kentucky coffee tree may live to be about 100 years old.
A legume, the Kentucky coffee tree is actually a flowering plant that produces pods containing seeds that are otherwise edible apart from the toxic substance called cystine that it contains, which is poisonous to humans unless the seeds are roasted thoroughly.
The Kentucky coffee tree got its name because the early North American colonists used to make coffee out of the tree’s large seeds. The tree however has no relation whatsoever to the commercial coffee tree. Nevertheless, the Kentucky coffee tree is still considered a good alternative source of coffee.
Only the female Kentucky coffee tree may produce the seed pods, measuring six to ten inches long. These pods usually appear in late summer and sometimes last throughout the whole winter. Inside, the beans are packed in green gooey substance and protected by a hard, dark green-brown shell.
Today, the Kentucky coffee tree is commonly used as a shade tree on larger, ungroomed properties, such as parks, golf courses, and other large areas. The Kentucky coffee tree has also been identified as a close relation of the honeylocust with its furrowed, dark brown bark and large foliage and reputation for being a tough, messy tree.
The Kentucky coffee tree has preference for deep, rich bottomland alluvial soils. They are perfectly suited to urban settings. In addition, the largest specimens can be found mostly in moist hollows on soil made of limestone. However, the plant is tolerant of most soil types. For this reason, the Kentucky coffee tree is highly valued as a hardy tree used for landscaping.