The Structure of Gum Trees

Physical Structure

• The gum tree is deciduous and has potential height of 100 feet or more when growing in its native habitat. Cultivated trees have a mature height of 60 to 75 feet with a 40- to 50-feet spread. With a slow to medium growth rate, young gum trees achieve a height of 1 to 4 feet per year. The long-lived tree has an age of 150 to 300 years. Young gum trees have a conical structure that gradually turns rounded and pyramidal as the trees mature. The base of the trunk is slightly buttressed.

Foliage

• The glossy foliage of gums resembles maple foliage with its distinctly palmate, deeply lobed, star-shaped form. The leaves measure 4 to 7 inches in diameter and appear alternately on the stems. New foliage starts to appear on tree during late spring. The undersides of the dark green leaves is a lighter color and fuzzy textured, producing an unpleasant aroma when crushed. The foliage assumes bright shades of red, yellow and orange before falling in autumn.

Flower and Fruit

• The gum tree blooms with inconspicuous flowers during spring followed by hard, round fruit. The spiny, golf ball-sized tree fruit is 1 to 1 ½ inches in diameter. Growing on long stems, the young fruit is green but eventually turns brown with age, often staying on the tree well through January. Every fruit consists of a two-celled capsule, each containing a pair of black seeds. The trees start to produce fruit at the age of 15 to 20. The fruit usually splits to release seed before it falls from the tree.

Cultural Requirements

• Plant the tree in a fertile, well-drained, preferably acidic soil. The tree adapts well to a variety of soil types including slightly compacted. Gums are sensitive to urban stress such as pollution and do not thrive in urban settings. Select a site receiving full to partial sun for best growth. The tree has moderate tolerance for drought and is hardy in USDA Zones 5 to 9.