Wednesday, March 28, 2012

The Valuable Redbud Tree

Spring's arrival is always marked in the Tennessee Valley by the pink-magenta blooms of the redbud, Cercis canadensis. This spreading small tree is found from southern New England all the way to Mexico. In the west, the western redbud, C. occidentalis, is the equivalent species, though it is smaller and more tolerant of drought than its eastern cousin. Gardeners throughout much of North America, therefore, have access to a redbud tree that is native to their region. The most frequently seen alternate name is Judas tree.

A large Eastern Redbud glows in morning light.
Rarely growing larger than 25-30 feet, the eastern redbud eventually develops an umbrella-like canopy 20 feet or more in width. It tolerates shade, and although it is abundant in the rich bottomlands of the Mississippi Valley, it grows very well on leaner soils of the Ridge and Valley region of East Tennessee. The interstates are lined with them.

Because the tree is a legume and develops a deep tap root, it improves the soil in which it grows. Creating a flower bed underneath a redbud is typically successful, as long as the flowers will tolerate the dappled shade cast by the limbs. The symbiotic bacteria that live in nodules on the tree's roots add nitrogen to the soil, and the annual leaf fall provides minerals pumped up from deep in the subsoil through the tree's extensive root system.

Several cultivated varieties of redbud species exist. All typically offer desirable features not always present in wild trees. The shade and intensity of coloration varies considerably from one tree to the next, for example. Nevertheless, we have produced some fine trees by selecting self-sown seedlings of the tree shown in the above picture, a mature specimen that was here long before the house was built. Seedlings are usually large enough to bloom by their fourth year of growth. They grow rapidly to about 15 feet, and then slow down and spread out. Careful pruning of young trees will yield the most attractive specimens. Once they are blooming size, little additional pruning is needed. Older trees will shed limbs, pruning themselves.

Water stress can lead to browning of the leaves and premature leaf loss, but the redbud is remarkably tolerant of drought once established. It flourishes best, however, with an inch of water a week during the growing season. Fertilization is not needed, as a rule.

Many gardeners are familiar with the redbud, but I am willing to bet that few know its culinary properties. Native Americans collected the flowers and ate them raw or cooked in water. The shiny, brown seeds were roasted and eaten. Modern analysis indicates the seeds contain healthy fatty acids, while the flowers contain anti-oxidant compounds. Green twigs of the eastern redbud were also used by Appalachian settlers to flavor game-based stews and roasts, earning the plant the colloquial name "spicewood." It would be worth trying with lamb, turkey or bison. (In case you are short on opossum or groundhog.)

Redbuds can be propagated from both softwood and hardwood cuttings, and by seed. Freshly collected seed should be placed in hot (99 degrees F) water and allowed to cool overnight before sowing. They will germinate quickly. Field grown specimens are preferable because containers resrtict the taproot, preventing the best growth.

If you are looking for a small tree for your property, the redbud offers numerous advantages, and is a long-lived, trouble-free species.

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