Celtis occidentalis - American or Common Hackberry (Ulmaceae) ------------------------------------------------------------------------------------------------------------------ Celtis occidentalis is a tough tree for urban or rural -lateral stems often die back a few inches to give a sites, growing rapidly to provide shade, windbreak, ragged appearance to the ends of branches and/or erosion control under stressful conditions. Trunk -light gray to gray-green FEATURES -very corky to warty ornamental bark, slowly Form becoming platy with age -large deciduous tree -often to 3' or more in diameter on old trees, with -maturing at 70' tall x significant basal flair 50' wide -wood is much stronger than Silver Maple (another -upright oval growth quick shade tree) habit in youth, quickly losing its central USAGE leader and becoming Function rounded to irregular in -shade tree (for highly stressed, poor soil, or wet soil habit with age sites where rapid growth is needed), deciduous -rapid growth rate windbreak, pioneer invader tree Culture Texture -full sun -medium texture overall in foliage and when bare -prefers moist soils but (fine-textured twigs, but bold and irregular branching is adaptable to many pattern) adverse conditions, -average density in foliage but thick when bare including wet or dry Assets sites and poor soils -urban tolerant (dry sites, soil compaction, pollution, -propagated primarily wind, heat, acid or alkaline soil tolerant), ornamental by seed but also by rooted stem cuttings or grafted bark, rapid growth, adaptable to wet sites onto seedling understock Liabilities -Elm Family, with several diseases and pests, but not -poor autumn color, gets very large for urban areas including Dutch elm disease (in canopy height and width, and trunk girth) -witches' broom is a dense clustering of miniature -leaf (nipple gall) and twigs (witches' broom) stems and foliage, caused by the combination of a cosmetic diseases mite and a fungus -causes bird waste litter in early autumn due to their -nipple gall on summer and autumn foliage is a fruit cosmetic leaf disease overconsumption -chlorotic foliage in summer is indicative of alkaline -shedding twigs soils that result in manganese deficiency to the tree and occasional -moderate availability, usually B&B twigs winter -often a volunteer tree in waste sites, fence rows, etc. dieback that is left for shade or windbreak function (or is too -chlorotic foliage big to conveniently cut down) in alkaline soils is Foliage the result of -alternate arrangement; medium green in color manganese -serrated, ovate, with the base of the leaf skewed deficiency (unsymmetrical or lop-sided, like the foliage of most Habitat Elm Family members) -Zones 2 to 9 -often gets nipple gall in spring -Native to -autumn color yellowish green to green floodplains of the Eastern U.S. SELECTIONS Alternates -large shade trees for stressful sites where poor environmental conditions exist (Ailanthus altissima, Fraxinus americana, Gleditsia triacanthos var. inermis, Morus rubra, Ulmus parvifolia, etc.) -large shade trees with ornamental bark (Betula Flowers nigra, Fagus sylvatica, Fraxinus americana, -greenish-yellow in Apr.-May, a mixture of Gleditsia triacanthos var. inermis, Ulmus parvifolia, staminate, pistillate, and perfect flowers, giving a fine etc.) texture and lime color to the tree in early spring as Cultivars – Variants – Related species the foliage begins to emerge -Celtis occidentalis 'Chicagoland' - maintains a Fruits single, relatively straight trunk throughout most of its -greenish small round fruits in leaf axils, changing to life orange or purple in color at maturity in Sept.-Oct. and -Celtis occidentalis 'Prairie Pride' - possesses a devoured by birds uniformly oval canopy, lustrous dark green thick Twigs foliage, stems that do not develop witches' broom, -light gray, zigzag and irregular in growth pattern and low fruit set -sometimes affected with witches' brooms -stems have no terminal buds and are often knobby.