Introduction
The tree forms a rounded vase reaching a height of 40 to 50 feet, is a moderately-rapid grower. The mature bark is light gray, rough and corky and the small fruit turns from orange red to purple and is relished by birds. The fruit temporarily stains walks but this cultivar fruits far less than the species. Leaves are wider than Celtis laevigata and more serrated. Hackberry may recover from transplanting from a field nursery slowly due to the extensive, coarsely branched root system, but this can be overcome by planting from containers.
Credit: Ed Gilman
General Information
Scientific name: Celtis occidentalis
Pronunciation: SELL-tiss ock-sih-den-TAY-liss
Common name(s): 'Prairie Pride' common hackberry
Family: Ulmaceae
USDA hardiness zones: 3B through 9A (Fig. 2)
Origin: native to North America
Invasive potential: weedy native
Uses: parking lot island > 200 sq ft; urban tolerant; street without sidewalk; reclamation; shade; highway median; tree lawn 4-6 feet wide; tree lawn > 6 ft wide
Availability: not native to North America
Description
Height: 40 to 55 feet
Spread: 40 to 50 feet
Crown uniformity: irregular
Crown shape: round, oval
Crown density: dense
Growth rate: fast
Texture: medium
Foliage
Leaf arrangement: alternate (Fig. 3)
Leaf type: simple
Leaf margin: serrate
Leaf shape: elliptic (oval)
Leaf venation: pinnate, bowed
Leaf type and persistence: deciduous
Leaf blade length: 2 to 4 inches
Leaf color: green
Fall color: yellow
Fall characteristic: showy
Flower
Flower color: green
Flower characteristics: not showy
Fruit
Fruit shape: round
Fruit length: less than .5 inch
Fruit covering: fleshy
Fruit color: red, purple, black
Fruit characteristics: attracts birds; not showy; fruit/leaves a litter problem
Trunk and Branches
Trunk/bark/branches: branches don't droop; showy; typically one trunk; thorns
Pruning requirement: needed for strong structure
Breakage: resistant
Current year twig color: green, brown
Current year twig thickness: thin
Wood specific gravity: 0.53
Culture
Light requirement: full sun, partial sun, or partial shade
Soil tolerances: clay; sand; loam; acidic; alkaline; well-drained; extended flooding
Drought tolerance: high
Aerosol salt tolerance: moderate
Other
Roots: can form large surface roots
Winter interest: yes
Outstanding tree: no
Ozone sensitivity: unknown
Verticillium wilt susceptibility: resistant
Pest resistance: resistant to pests/diseases
Use and Management
Hackberry grows naturally in moist bottomland soil but will grow rapidly in a variety of soil types from moist, fertile soils to hot, dry, rocky locations in the full sun. Hackberry is tolerant of highly alkaline soil whereas sugarberry is not. It is wind, drought, salt, and pollution tolerant once established and is considered a moderately tough, urban-tolerant tree. Skilled pruning is required for the species several times during the first 15 years of life to prevent formation of weak branch crotches and weak multiple trunks. However, this cultivar reportedly forms a central trunk better than other hackberries and unlike the species, many branches originate from the trunk. This should make it easier to train into a strong, well-formed urban tree.
The species was extensively used in street plantings in parts of Texas and in other cities as it tolerates most soils except extremely alkaline (pH > 8), and grows in sun or partial shade but branches may break out from the trunk if proper pruning and training is not conducted early in the life of the tree. Further testing is needed to determine if this cultivar resists breakage better than the species. Even slight injury to the trunk and branches can initiate decay inside the tree. If you use this tree, locate it where it will be protected from mechanical injury. If used along streets where the trunk would be injured, internal root may develop.
Prune and thin the canopy to prevent formation of weak, multi-trunk trees. The tree is susceptible to breakage in ice storms.
Pests
The most common insect on hackberry causes the hackberry nipple gall. A pouch or gall forms on the lower leaf surface in response to feeding. There are sprays available if you care to reduce this cosmetic problem.
Scales of various types may be found on hackberry. These may be controlled with horticultural oil sprays.
Diseases
Many native and planted trees died slowly from an unknown cause.
Several fungi cause leaf spots on hackberry. The disease is worse during wet weather but chemical controls are seldom needed.
This cultivar is mostly resistant to witches' broom. Witches' broom is caused by a mite and powdery mildew. The main symptom is clusters of twigs scattered throughout the tree crown. Prune out the clusters of twigs when practical. Most common on Celtis occidentalis.
Powdery mildew may coat the leaves with white powder. The leaves may be uniformly coated or only in patches.
Mistletoe is an effective colonizer of sugarberry, which can kill a tree over a period of time. It appears as evergreen masses several feet in diameter scattered about the crown.
