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HACKBERRY. 

 Celtis occidentalis, Linnaeus. 



GENUS DESCRIPTION The genus Celtis comprises about 60 species, of which number 

 about 9 are native to North America and 1 to Pennsylvania. Representatives of this genus are 

 found in temperate and tropical regions of both the eastern and western hemispheres. Another 

 species known as Rough-leaved Hackberry (Celtis crassifolia, Lamarck) is also reported from 

 3 counties in this State. The leaves of the latter are very rough and the fruit is subglobose. 



FORM Usually a small tree 20-35 ft. in height, but single specimens with a height of 

 8C ft. and a diameter of 30 inches have been reported for this State. In the South it 

 becomes larger. Trunk usually short. Crown rather wide-spreading and round-topped. Witches' 

 brooms are frequently found upon it. 



BARK Grayish -brown, sometimes as smooth as Beech bark, others have very rough bark 

 due to harsh, warty projections. Younger branches are dark brown to reddish-brown in 

 color. See Fig. 102. 



TWIGS Slender, somewhat shiny, occasionally slightly downy, brownish, covered by scattered 

 raised and often longitudinally-elongated lenticels; contain chambered white pith. 



BUDS Alternate, 2-ranked, small, often malformed and swollen, i of an inch long, ovate, 

 sharp-pointed, appressed, covered with 3-4 visible and closely overlapping bud-scales. Bud- 

 scales sometimes longitudinally-striated and dark margined. Swollen buds caused by insects. 



LEAVES Alternate, simple, ovate, 2-4 inches long, acute at apex, obliquely rounded at base, 

 serrate on margin, entire near base, rough on upper surface, with prominent primary veins. 

 Petioles slender, slightly hairy and grooved. 



LEAF-SCARS Alternate, 2-ranked, small, semi-oval, at or almost at right angles to twig 

 on projections of twig, with 1-8 bundle-scars. 



FLOWERS Appear about May. Three kinds, staminate, pistillate, and perfect, may be 

 found. They are greenish and borne on slender drooping stalks. 



FRUIT A berry-like, dark purple, globular drupe about i-J of an inch in diameter, tipped 

 with persistent style and borne on a slender stalk. Matures about September and often 

 persists into winter. 



WOOD Ring-porous; rays very distinct; pores in summer wood arranged in tangentially 

 wavy bands: heavy, not strong, coarse-grained, yellowish. Weighs 45.51 Ibs. per cubic foot. 

 Used for fencing, crates, boxes, slack cooperage, hoe handles, agricultural implements. 

 Resembles Ash. Most mills sell it as Ash. 



DISTINGUISHING CHARACTERISTICS The Hackberry, also known as Sugarberry, Nettle- 

 tree, Hoop Ash, and Hack-tree, can be distinguished by its chambered pith, berry-like fruit, 

 warty or corky bark and disfigured twigs and buds. Abnormally swollen twigs are due to 

 stings of gall insects. Witches' brooms are also common and very distinctive. The leaves 

 resemble those of the Elms only are sharper pointed. 



RANGE Its range covers about 2,000,000 square miles in the United States, extending 

 over the major part of the United States east of the Rocky Mountains. 



DISTRIBUTION IN PENNSYLVANIA Occasional throughout the State. Nowhere abundant. 

 Sometimes only a single tree is known in a locality. Large specimens are found in North- 

 ampton and Montgomery counties. 



HABITAT Prefers rich moist soil, but also grows on gravelly uplands. Does not form 

 pure stands, but usually occurs solitary. 



IMPORTANCE OF THE SPECIES The Hackberry is of little commercial importance in 

 this State since it is a rare tree and seldom reaches a large size. Only a few large trees 

 have been recorded in this State. It cannot be recommended as a timber tree, neither 

 has it any specially attractive ornamental qualities. Its continuity is insured because the 

 birds carry the seed far and wide. 



