Showing posts with label kentucky coffee tree. Show all posts
Showing posts with label kentucky coffee tree. Show all posts

Thursday, January 19, 2012

Kentucky Coffee Tree

A fine specimen of a Kentucky coffee tree, Gymnocladus dioicus, towers skyward at Columbus, Ohio's sprawling Green Lawn Cemetery. The 360-acre Green Lawn - 2nd largest cemetery in the state! - is a virtual arboretum, with some 90% of the Buckeye State's native tree species in residence. Many of the natives, such as this coffee tree, were not planted; rather they are part of the indigenous flora that has been incidentally conserved by the establishment of the cemetery.

Of all of the trees at Green Lawn, the Kentucky coffee trees may be my favorites. They may seem a bit homely, perhaps, especially when contrasted with the stately columnar trunks of nearby tulip trees, or the soft elegance of eastern hemlocks. In the company of the runway model trees, the coffee trees might be considered ugly ducklings but to me that is part of their allure.

If you were to paint the quintessential spooky Halloween scene - full moon in the corner, haunted house in the backdrop, bat winging by, owl glaring from a tree - it's the Kentucky coffee tree that you'll want to star as the centerpiece. Its wildly contorted branches twist and jag crazily, and the thick stubby twigs create the effect of ill-kept witch's brooms.

The trunk is broken into long furrows, as if tectonic plates of bark have collided and ruptured against one another. Like the rest of the tree, even the bark has a messy charm to it.

The long persistent seed pods instantly reveal the coffee tree's allegiance to the Fabaceae: the bean family. Stunted and stubby like the branches they hang from, coffee tree pods suggest fat little locust seed pods. You'll only find the fruit adorning female trees, though - the specific epithet of this plant, Gymnocladus dioicus, means = diocecious. Dioecious plants have separate male and female plants, so if you've got a Kentucky coffee tree that never produces fruit, it's likely a male.

Your blogger took the liberty of plucking a pod from the Kentucky coffee tree, and it protested not a bit.

Split open, we can see the thick greenish-yellow pulp that the fingernail-sized seeds nest in. The tree's common name stems from the sometimes use of the seeds as a coffee substitute, at least in days gone by. I would NOT recommend brewing up drink from this stuff, though - the seeds, leaves, and other parts of this tree are at least mildly toxic and you'll get more bang than you probably wanted.

Ohio Division of Forestry forester Brian Riley holds a Kentucky coffee tree leaf. I took this photo at Green Lawn several summers ago, and if you visit these trees during leafout, you'll be rewarded by the spectacle of the largest leaf of any Ohio plant. The whole assemblage in Brian's hand is just one very large leaf, and in botanicospeak it is termed twice pinnate. Each unit is a leaflet, and collectively it is all of those little leaflets that comprise the leaf in toto.

Kentucky coffee trees are not especially common, and never form dominant stands, at least insofar as I have seen. They prefer alkaline soils and are most likely found where limestone beds jut near the earth's surface in central and western Ohio. Green Lawn Cemetery is without doubt one of the best places to easily find coffee trees and admire their rather homely charms.