American Yellowwood (Cladrastis kentukea )
This tree is called “Yellowwood” because the freshly-cut heartwood is a muted to brilliant yellow color, and the wood is known to yield a yellow dye. The American Yellowwood is a native tree, but has never multiplied in large numbers in the wild. In fact it is quite rare in the wild and always has been. Its range is in the Appalachian Mountains in western North Carolina, eastern Tennessee, Arkansas and Missouri. Because this tree has nice bark and foliage and such a fantastic show of white flowers in early summer, it has become a popular landscape tree. The downside is that many folks consider this a problem tree because it does drop a lot of small branches, seedpods and leaves requiring fairly frequent cleanup. It is also a tree that does require some careful pruning in the beginning to avoid serious storm damage later in its life. With all that, the flowers are so breath-taking that for many it is well worth the trouble.
This medium to large deciduous tree is usually low branching with a broad, rounded crown of delicate branches that are upright and spreading. If it is not pruned it will have a short main trunk with major branches starting within 6' of the ground. The gray bark is very smooth and thin, making it vulnerable to those teenagers needing to record their true love with the aid of a pen knife.
Yellowwood has alternate, pinnately compound leaves with 5 to 9 leaflets (usually 7) along the stem that is 8 to 12" long. The leaves are green on the upper surface and paler below. The fall color for this tree is quite showy with a soft mix of yellow, gold and orange.
It is in the late May to early June when this tree becomes the star. The display of pea-like creamy to white flowers borne on 8 to 14 inch long hanging clusters become a standout in any landscape. They resemble the blooms of a wisteria. They are not only beautiful but they are fragrant as well. As might be expected when the Yellowwood is in bloom all the honeybees in the neighborhood come on board to collect the nectar. These trees don’t display their flowers without some delays. The tree usually does not begin to flower until it is at least ten years old, and some reports of no flowers until 25 years exist. Then when the show is on, it is not on every year. The truly spectacular floral displays come in cycles of every two to five years. But when it is on it is gangbusters. The fruit of the Yellowwood is not particularly ornamental, but it does need cleaning up in the winter. The fruit are flat brown pods, 2 to 4 inches long that ripen in early fall and then persist into the winter when they fall off the tree.