Hackberry (Celtis occidentalis)

A deciduous tree from the Elm Family (Ulmacea)

Hackberry, also known as Common Hackberry, Northern Hackberry, or American Hackberry, is present throughout the upper half of the eastern United States, the Great Plains, and southern Canada, including almost all of Ohio. It is a tree that frequents fencerows, fields, and wastelands, and grows naturally near bodies of water, including floodplains and drainage ditches. It is easily recognizable from a distance by its light gray, warty bark on massive trunks, coupled with its rapid growth rate and large size.

It easily grows to 80 feet tall by 60 feet wide when found growing in the open, often with a single trunk that quickly branches into several spreading huge branches that form an ascending or spreading canopy. As a member of the Elm Family, it is related to the Elms and other Hackberries.

Planting Requirements - Hackberry prefers but can adapt to a variety of sites, including soils that are wet or dry, clay or rocky, rich or poor. It performs well emerging from limestone outcrops, although its growth will be slower and its size diminished. It is also very pollution tolerant, as it thrives in the smog and dirty water runoff of cities.

Potential Problems- Hackberry has a host of foliar and twig diseases, all of which are cosmetic in nature (ugly, but not life-threatening). These include nipple gall and powdery mildew (affecting foliage) and witches' broom (clusters of twiggy growth, looking similar to the effects of Sycamore anthracnose). Chlorosis can occur in high pH soils on occasion. In many urban situations, Hackberry is a tree that may invade sites as an "uninvited guest" and is allowed to remain until it gets to be too big of a problem to ignore any longer (rather like Tree-of-Heaven, Boxelder, Common Buckthorn, Amur Honeysuckle, and other woody "weeds").

Its medium growth rate makes it a good candidate for areas in need of erosion control or quick shade. As a tree for tough sites, it has a rather coarse appearance and large ultimate size that discourages its usage as an intended landscape shade tree, but several cultivars are in limited usage with a more refined branching structure and leaf appearance. It is found in zones 3 to 9, growing in full sun.

Leaf Identification Features

Hackberry, as a member of the Elm Family, has alternate leaves with serrations on the margins, and leaf bases that are asymmetrical around the petioles.

Fall color is green to chartreuse and usually insignificant.

Other Identification Features

Hackberry has several cosmetic diseases and pests, none of which slow down the growth rate of this vigorous species. Nipple gall, caused by an insect, displays bullet-like projections on the lower leaf surfaces of leaves.

Witches' broom is a dense clustering of miniature stems and foliage, caused by the combined effects of a mite and a fungus. Both serve as excellent identification features for Hackberry, although Mulberry can also have witches' brooms.

Most people do not notice the small, green flowers of Hackberry in early to mid-spring, as they are easily lost in the expanding foliage of this polygamo-monoecious species (having male, female, and perfect flowers all on the same tree). The female and perfect flowers develop into small, rounded, green fruits throughout the summer that become dark green, purple, or brown fruits by late autumn. These are usually consumed in great quantities by birds in mid- to late autumn, but a few may survive the winter and still be present by the following spring.

A year-round feature of Hackberry is its warty, light gray bark; the "warts" are actually projections of cork. With age, the lower portion of its massive trunk becomes platy, and slowly merges as a basal flare with the huge, shallow surface roots near the trunk. When the wood of Hackberry is cut or split, it is the most white-colored of any common hardwood.