Sunday, August 16, 2009

Gymnocladus dioica - Kentucky Coffee Tree

Good call, Justin and Tom. It is Gymnocladus dioica, and almost certainly a cultivar (cultivated variety). The leaflets are smaller than the typical species. There is also a Gymnocladus chinensis used in landscaping, but it normally has many more pairs of leaflets and the leaflets are more narrow.

In northern Indiana, Kentucky Coffee Tree is occasional in rich mesic forests and bottomland forests along streams. It is not common here. The large, distinctive bean pods fall off in spring and are gathered by wildlife. They bear a rich, pleasant coffee-like smell. It would be interesting to know how they were used by Native Americans and European settlers. Folklore mentions a coffee-like drink, and I'm confident there were other uses. The seeds are extremely hard and spend several years in the soil before germination. However, if scarified they sprout readily.

The lumber has fantastically beautiful grain similar to White Ash, and is used in cabinetmaking. Lumbermen and cabinetmakers call it "Coffee Nut."

During drought, the leaflets turn their edges toward the sun. This may be the only tree in Indiana with bipinnate leaves.

1 comment:

Justin Thomas said...

The early bird got the worm.

It is interesting that you mention the scarification of Coffee Tree. This is one of the species of trees that was more common during the Pleistocene. It is thought to have been eaten by Pleistocene megafauna such as Giant Sloths and that a trip through the gut of a large mammal provides the scarification (acids I guess) needed to promote germination. Thus it is now considered, along with Honey Locust and Osage Orange/Hedge Apple, to be an ecological anachronism. For futher reading on this fascinating subject may I suggest the book "The Ghosts of Evolution" by Connie Barlow.