Our Kentucky coffeetree update, 10/1/13

Gymnocladus dioicus, the Kentucky Coffeetree is native to Iowa with a grain similar to red oak after it's milled. It was a tree that my dad sought out for its lumber for his projects and I made a simple bookcase out of coffeetree for my wife for our second Christmas together.

Although a member of the legume family (Fabaceae), Kentucky coffeetree is not a nitrogen “fixer”. It is a medium to large, round-barked, native deciduous tree reaching heights of 18 to 30-m with a spread of 12 to 15-m. In open areas, the tree produces an open, rounded crown, but in native woods it grows to 23-m with few branches.

Kentucky coffeetree can be found growing in association with sweetgum, tupelo, oaks, and hickories, also black walnut, basswood, elm, and pawpaw in temperate forests.

We added our coffetrees starting last year when True Blue Sam and his Mrs. gathered, cleaned and sent us a good supply of seed in late winter of 2012.

We tried a couple of methods of propagation with varying degrees of success.

1. We planted several by seed and "caged" them with hardware cloth and soup cans after splitting the bottom of the cans. Of the thirty or so, only a couple sprouted by summer. I found ant hills at several locations and decided to dig a couple up. I discovered sprouts but little root development. I'm assuming the ants used these as a good food supply.
2. Using a technique called scarification, I then planted the seeds in pots in March, 2012. I used a small triangular file to breech the hard shell of the seed. Any seed planted deeper than the seed itself had a tendency to rot in the shell and I had a germination rate of 90%. I used both fiber pots and a burlap lined pot and transplanted after the root breeched the 6" pots. Both worked well.

I transplanted many by mid-May 2012, but the harsh drought limited growth and despite our best efforts to water we lost about 70%. No fall transplants survived the winter. The very little snow cover and below average temperatures did not help us as many of our deciduous transplants did not make it.

However, one coffeetree that has thrived is planted in the southeast corner of our northern plot of trees.

 June 23, 2012

This tree grew very well during 2012 and I had to put a bigger woven wire cage around it last fall. A very wet 2013 spring with a two-day span of 14+ inches of rain in April set us up for the summer.

The same tree May 19, 2013

It showed up this spring as a dead twig but by middle of May there was a new sprout growing along side.

June 30, 2013

By late June, the central leader reached about 6-8 inches with the compound leaves giving us the impression of another six inches or so.

August 31, 2013

Another dry summer with only an inch of rain during June, July and August. This meant we had to haul water again but the cooler conditions may have contributed to this explosive growth. This tree towers over the other coffeetrees that are about 6-8 inches. Sam and his mom stopped by and snapped the picture above.

September 22, 2013

A hot and still dry September added another 6+ inches. It's now topping off at about 30 inches as it reaches the top of this woven wire cage. To prevent girdling by rodents (which killed a few of the other coffeetree and maple seedlings), I made a small hardware cloth cage to surround our tree trunk.

Nature is making this our showcase tree and I have no idea why. Luck, environment, soil type all contributed to its success. The only exception that can be noted is that a groundhog tilled the soil all around it apparently without damaging the root structure. Aeration may have been the difference.

These coffeetrees represent the memories I have of working with my dad in his workshop and our growing friendship that have started David over at True Blue Sam, his mother Bea and others in recent years. Hopefully this coffeetree will grow and give our future generations a 80+ foot tree and a good supply of milled lumber.