One of the more interesting trees that can be found in the woods along the Lehigh Portland Trails is Gymnocladus dioicus, known as the “Kentucky Coffee Tree”. The tree is characterized by large dark brown fruit pods that mature during the autumn and can remain on the tree throughout the winter. Each pod is 3 to 6 inches long by 1.5 to 2 inches in width, and contains several large seeds immersed in a sweet green gelatinous green pulp. Every part of the tree, including the leaves, seeds, and pulp, is toxic, and is thus avoided by wildlife.
This tree is an ecological anachronism. It evolved as a food for megafauna of the Pleistocene epoch, which ended about 12,000 years ago. At that time, large herbivores such as mastodons and rhinos roamed North America. These creatures were able to consume the toxins, and craved the gooey pulp. The seeds were consumed as well, eventually passing through the animals and dropping wherever they happened to wander. That was how the tree spread its seeds.
The Kentucky Coffee Tree is native to large swaths of the midwestern United States, including eastern Kansas. It is now increasingly rare, since the animals that it relied on for seed distribution have long been extinct.
There is a good stand of several trees located on the Lehigh Portland Trails property. It is not known how the trees came to be there, since much of the land was effectively scoured by the quarrying operation. The USDA reports that “Kentucky coffeetree was formerly planted around farmsteads”, so perhaps it came from a nearby homesite, of which there are several on and near the property.
And the name? It’s called a “coffee tree” because the seeds can be roasted (which neutralized the toxicity), ground, and used as a replacement for coffee, though it is reportedly a poor substitute. Native Americans also used roasted seeds for food, used parts of the tree for medicinal purposes, and used the seeds for games and jewelry.