Comprehensive DescriptionRead full entry
DescriptionThis medium-sized tree is 30-65' tall at maturity, forming a short trunk that soon branches and subdivides into a rounded crown. On old trees, trunk bark is light gray and pebbly, while on young trees it is light gray and smooth. Branches are usually gray and smooth, although sometimes they are brown. Twigs are light gray or brown, glabrous, and covered with scattered white lenticels. Often, the trunk and larger branches of older trees are covered with lichens or moss. Alternate compound leaves up to 1' long occur along the twigs; these leaves are usually odd-pinnate with 7-9 leaflets. The leaflets are arranged alternately along the rachis (central stalk) of each compound leaf; they are not directly opposite from each other. Individual leaflets are 3-4" long and and 1½-2¼" across; they are ovate or obovate, smooth along their margins, and pinnately veined. The upper leaf surface is yellowish green to medium green and glabrous, while the lower surface is pale green and hairless to pubescent. The slender petiolules (basal stalklets) of the leaflets are short (about ¼" in length), light green, and glabrous. The petioles of the compound leaves are 3-6" long, light green, and glabrous; they have swollen bases that encircle (or nearly encircle) the buds. The buds are brown and hairy. Drooping panicles of white flowers about 6-14" long and 3-6" across develop toward the tips of twigs; they are more broad at their bases than their tips. The branches and pedicels of each panicle are light green and glabrous. Individual flowers are about 1" long; each flower has a pea-like floral structure consisting of an upright banner (upper petal) and 2 forward projecting wings (2 lateral petals) that enclose a narrow keel (2 inner petals that are appressed together). These petals are white. At the base of each flower, there is short tubular calyx with 5 teeth that is light green. The reproductive organs consist of 10 separate stamens and a pistil with a single style. The pedicels are about the same length as the flowers. The blooming period occurs during the late spring for about 2-3 weeks. The flowers are fragrant. Individual trees bloom abundantly about once every 3-4 years. The flowers are replaced by flattened seedpods that are 2-4" long, ¼-¾" across, dark brown, and glabrous at maturity. Each seedpod contains 0-6 seeds; the lateral sides of the seedpods are often undulate and partially constricted between the seeds. The root system of young trees forms a taproot. During the autumn, the deciduous leaves become yellow or golden yellow.