Common Name: black gum
Native Range: Eastern North America
Zone: 3 to 9
Height: 30.00 to 50.00 feet
Spread: 20.00 to 30.00 feet
Bloom Time: May to June
Bloom Description: Greenish white
Sun: Full sun to part shade
Water: Medium to wet
Suggested Use: Shade Tree, Street Tree, Rain Garden
Leaf: Good Fall
Tolerate: Clay Soil, Wet Soil
Easily grown in average, medium to wet soils in full sun to part shade. Prefers moist, acidic soils. Tolerates poorly-drained soils and can grow in standing water. On the other end of the spectrum, tolerates some drought and adapts to some dryish soils, at least in the wild. Long taproot precludes moving established trees. Female trees need a male pollinator to set fruit.
Sour gum is a slow-growing, deciduous, Missouri native tree which occurs in a wide range of soils south of the Missouri River in the southeastern quarter of the State. It is primarily a lowland tree found in low wet woods, bottomlands and pond peripheries, but also can be found on dry rocky wooded slopes and ravines. A stately tree with a straight trunk and rounded crown (more pyramidal when young) that typically grows 30-50' tall, but occasionally to 90'. Primarily dioecious (separate male and female trees), but each tree often has some perfect flowers. Small, greenish-white flowers appear in spring on long stalks (female flowers in sparse clusters and male flowers in dense heads). Although flowers are not showy, they are an excellent nectar source for bees. Flowers give way to oval, 1/2" long fruits which are technically edible but quite sour (hence the common name). Fruits mature to a dark blue and are attractive to birds and wildlife. Spectacular scarlet fall color. Obovate to elliptic, entire to slightly toothed leaves (to 5" long) are dark green above and paler below. Sometimes commonly called black tupelo. The closely related water tupelo (Nyssa aquatica) is a tree most often seen growing in standing water in swamps and bottomlands in the lower Mississippi valley and southeastern U.S. coastal areas, either in pure stands or in combination with bald cypress, water oaks and swamp cottonwoods.
No serious insect or disease problems. Some susceptibility to leaf spots, canker, rust, leaf miner and scale.
Excellent ornamental shade tree for lawns or street tree. Also grows well in moist woodland gardens or naturalized areas or in low spots subject to periodic flooding or in boggy areas. Although slow-growing, it still needs to be sited in an area which affords plenty of room for future growth, particularly since it is so difficult to transplant.