The American yellowwood, Cladrastis kentukea, formerly named Cladrastis lutea, is somewhat rare to find growing natively in the landscape or available in the garden center. Why this is I am not really sure, but I suspect it is because this tree has branches that grow low to the ground, with a tendency to have poor branching angles. This poor branching makes it harder to manage in the nursery and makes it more susceptible to injury and breakage in the garden.
Despite its rarity, American yellowwood can be a beautiful, healthy part of your garden. This medium-sized tree grows only to a height of 30 or so feet and is equally or slightly wider than its height. This medium height makes it a perfect size for smaller gardens or city streets where a maple or an ash would be much too large.
Yellowwood has several other excellent characteristics, like its fragrant white flowers. The flowers are borne on an 8-14-inch-long drooping panicle and appear in early to mid-May. They cascade off the tree like the flowers of a wisteria. This tree tends to bloom heavily one year, bloom lightly the next, and then back to blooming heavily. This alternate-year blooming can be frustrating, but even in light bloom it’s spectacular.
The yellowwood also has smooth gray bark like that of a beech. In the winter, at first glance you may think it is a beech, but the difference in shape is a dead giveaway. The heartwood is a bit unusual because it is yellow, as its common name tells us, but you would never know this unless you cut one down, prune a branch, or sever a root.
My favorite characteristic is the leaves. The large 8-12-inch-long compound leaves have seven to nine leaflets, open a sunny yellow-green, and change to a bright grassy-green for the summer. Many deciduous trees have leaves that are dark or bluish green, so it’s great to see a tree that is quite different. In the fall the leaves turn a wonderful and consistent yellow and drop slowly from the tree.
This is definitely a tree that asks you to come near it. In the spring you will want to pick a few of its fragrant flowers. In the summer you will appreciate walking under its shade. In the fall you will be drawn to simply sit underneath it and think for a moment while watching the leaves slowly trickle down near your feet. In the winter each time you walk by you will reach out and touch the smooth gray bark.