This month’s tree spotlight is the Kentucky coffeetree (Gymnocladus dioica). The coffee tree is native to central and eastern North America.
Kentucky coffeetrees grow well in full sunlight and moist well drained soils. It can reach a height of 60-75 feet with a 40-50 foot crown spread. It is a very tolerant tree growing well in acidic, alkaline, moist, and rich soils. It is tolerant to drought and air pollution making it a great street tree. The coffeetree’s leaves, seeds, and pulp are poisonous and are toxic to wildlife, livestock, humans, and pests. Since it dioecioius with a male and female plants it is suggested to plant the male species to avoid the fruit. Although the seed pods are poisonous, when cooked they are safe to eat. Native Americans roasted seeds for food, and early settlers used the roasted seeds as a coffee substitute. You might suspect this is where it gets its name, but it’s not. The tree gets its name because the seeds look like coffee beans.
The Big Tree Program is a national initiative that tracks and records the biggest trees of each species across the country. The Vermont big tree program is based on the national program; its scoring system comprises 3 measurements: height, crown width, and circumference at breast height. The current champion Kentucky coffee tree is in West Castleton, Vermont. The last time it was measured in 2003, its height was 105 feet, it had an average crown spread of 26 feet, and its circumference at breast height was 6 feet 1 inches, with a diameter of 1 feet 11 inches.
Common names: American coffee bean, American coffee berry, American mahogany, coffee tree, dead tree
Height: 60-75 feet
Hardiness Zone: 3-8
Leaf: Alternate, bipinnately compound (meaning the initial leaflets are composed of multiple leaflets), very large leaflets 1 to 3 feet long, with numerous ovate 1 ½ to 2 inch leaflets, green above and slightly lighter underneath.
Flowers: Coffee trees are dioecious, meaning there are both male and female trees, male and female flowers are whiteish organized in long 3 to 4 inch branched clusters.
Fruit: Reddish brown flat pods, 3 to 8 inches long, 1 ½ to 2 inches wide, contains six or more dark brown seeds imbedded in a sticky pulp.
Twig: Stout, light brown with whitish patches, somewhat zigzag or wavy, large heat-shaped leaf scar.
Bark: Dark grayish brown, scaling, and developing deep scaly ridges as tree matures.
5473007- Vern Wilkins, Indiana University, Bugwood.org
0008362, 0008216 - Paul Wray, Iowa State University, Bugwood.org
5454540- Jason Sharman, Vitalitree, Bugwood.org
5500415- T. Davis Sydnor, The Ohio State University, Bugwood.org