Kentucky Coffeetree

Gymnocladus dioicus


Kentucky Coffeetree (photo: Bruce Marlin – Wikimedia)

The Kentucky Coffeetree is a moderately fast-growing tree, and male trees are often grown in parks and along city streets for ornamental purposes. The tree is typically long-lived, healthy trees living from 100 to 150 years.

From 1976 to 1994 the Kentucky coffeetree was the state tree of Kentucky, after which the tulip poplar was returned to that designation.

The bark is ash-gray and scaly, flaking similarly to black cherry, but more so. The flowers are dioecious, and the fruit is a hard-shelled bean in heavy, woody, thick-walled pods filled with sweet, thick, gooey pulp. Pod length ranges from 5 to 10 inches (130 to 250 mm); unfertilized female trees may bear miniature seedless pods.

The Kentucky Coffeetree is believed to be an example of evolutionary anachronism. The tough, leathery seed pods are too difficult for many animals to chew through (in addition to being poisonous) and they are too heavy for either wind or water dispersal. It is thus believed that the tree would have been browsed upon by now-extinct mammoths and mastodons which ate the pods and nicked the seeds with their large teeth, aiding in germination.

The Kentucky Coffeetree is considered a rare tree species. “Rare species are those that are so uncommon that they should be monitored to determine whether their populations are becoming threatened.” It is widely distributed, but rare.

References and Additional Information

[1]  Wikipedia:  Kentucky Coffeetree
[2]  University of Kentucky: Kentucky Coffeetree
[3]  Encyclopedia of Life : Kentucky Coffeetree