Yellowwood

Scientific Description: Yellowwood – Cladrastis kentukea - This small to medium sized tree is a member of the pea (or Fabaceae) family that has a rather restricted geolocation, including the area bounded by North Carolina, Kentucky, Oklahoma and Mississippi; it does well in hardiness zones 4 through 8. This is an excellent shade tree for small to medium yards and gardens.

The American yellowwood tree can achieve a height of 40 to 60 feet tall, an equal diameter, a rounded appearance, vibrant yellow foliage in the autumn, with hanging clusters of white flowers that bloom in May and that are fragrant during the day. Yellowwood tends to produce abundant flowers only appear every other or every third year.

Habitat Value: While this tree is tolerant to a wide assortment of pH, soil type, moisture and drought conditions, it does best in well-drained, deep soil that is moist and fertile, i.e., has an almost compost-like content.

Because of its striking flowers in the spring and its eye-catching foliage in the autumn, American yellowwood is a good selection for a specimen tree to add interest to any garden.

The branches from this tree tend to break quite frequently. Low forking branches should be pruned in the early life of the tree to reduce the breaking and splitting of the tree. In addition, a 3-inch-thick mulch layer from the stem to the drip line should be applied to the ground to ensure a moist root system.

The American yellowwood tree is susceptible to canker, mildew, root rot and verticillium problems.

Interesting information: The interior wood of this species is a remarkable yellow color.

Landscape Value: Tennessee is right in the heart of yellowwood’s natural range, and its tolerance of limestone cliffs and ridges puts it at the top of any tree list for Chattanooga. The size, habit, blooms, bark, rich green summer foliage, and yellow fall color of yellowwood make it a choice specimen for most any garden. The beautiful smooth gray bark in winter extends its value to year-round. Every year clients spot one of these blooming around the city and ask for one in their gardens. While it can suffer from the diseases listed above, horticulturalist Michael Dirr notes that very few problems are associated with this tree. The City of Chattanooga has successfully used it as a street tree on several streets around the city. 

By Matt Whitaker with WMWA Landscape Architecture