Celtis occidentalis (Hackberry): Ecology

Habitat: Although preferring moist, low-lying woods, this species also grows in dry, heavy soils or sandy, rocky soils, withstanding both alkaline and acid conditions. It is moderately fast-growing in good soils, hardy to zones 2 to 9 and can live up to 200 years.

Diseases: This species is resistant to Dutch elm disease and is often used as a replacement for the American elm tree (Ulmus americana). Although the hackberry suffers from no serious pest or diseases, insect-caused nipple galls on the leaf surface and clusters of upright branches forming witches' brooms, caused by insect mites and powdery mildew, often destroy the aesthetic appearance of the trees. The former can be controlled by spraying, and the latter-almost always associated with a tiny gall mite and powdery mildew fungus-can be removed by pruning. The hackberry lace bug, a sap feeder on the underside of the leaf surface, may cause bleaching of the leaves. In the fall, the adult insect sometimes bites humans, which may become a minor nuisance.

Distribution: Native to all of Iowa, this species is widely distributed throughout the eastern US, and just into extreme southeast Canada.