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SWEET GUM. 



Liquidambar Stryaciflua, Linnaeus. 



GENUS DESCRIPTION This genus comprises 3 species, 2 of which are found in Asia and 

 1 in North America. The latter is native to a small portion of southeastern Pennsylvania. 

 A few fossil forms are also known. The generic name, Liquidambar, is a mongrel, the fore 

 part of which is of Latin origin and means liquid and the latter part of Arabic origin and means 

 amber in allusion to the fragrant juice of the tree. 



FORM A largo forest tree usually from 50-75 ft. high with a diameter of 2-3 ft., but may reach 

 a heignt of 150 ft. with a diameter of 4-5 feet. In the forest the trunk is tall, clean, slightly 

 tapering, and bears a narrow head. In open grown trees the trunk is short, bearing rather 

 regular spreading branches which form a symmetrical and rather conical crown. 



BARK On old trunks grayish-brown, 1-li inches thick, deeply furrowed separating broad scaly 

 ridges. On younger trunks thinner and dark gray. 



TWIGS Rather stout, obscurely angular, at first rusty hairy, later smooth, light brown to 

 dark reddish-brown, roughened by raised leaf-scars and scattered, dark, raised lenticels and after 

 the second season often by corky-winged projections of the bark. Pith rather large, angular, 

 and very light brown. 



BUDS Alternate, more than 2-ranked, ovate to conical, blunt-pointed to sharp-pointed, glossy, 

 rich reddish-brown, fragrant when crushed, covered with about 6 visible ovate scales which 

 have a short-pointed apex, downy margin, and a rounded back. Lateral buds are sometimes 

 accessory. 



LEAVES Alternate, simple, star-shaped, 3-5 inches long, broader than long; base at right 

 angles to stalk or slightly heart-shaped; margin serrate, with 5-7 sharp-pointed divisions; when 

 mature bright green and shiny above, paler below. Leaf-stalks long and round. 



LEAF-SCARS Alternate, more than 2-ranked, raised, slightly inclined to twig, crescent- 

 shaped or broadly heart-shaped, with a dark surface, containing 3 circular bundle-scars which 

 are white on the periphery and dark in the center. 



FLOWERS Appear about April when leaves are partly developed. Staminate flowers green, 

 borne in terminal racemes, 2-3 inches long, covered with rusty hairs. Pistillate flowers green, 

 occur in heads borne oa long stalks originating in the axils of leaves. 



FRUIT A long-stalke'l spherical head made up of many capsules which have a spiny appear- 

 ance, about 1-1J inches in diameter, persists far into winter. Individual capsules often filled 

 with sawdust-like material which consists of abortive seeds. 



WOOD Diffuse-porous; rays distinct; rather heavy, hard, with interlocked grain, somewhat 

 difficult to work, reddish-brown with dark streaks, sapwood wide and white. Weighs 36.83 Ibs. 

 per cubic foot. Used for boxes, crates, furniture, interior finish, and extensively as a substi- 

 tute for Circassian Walnut. 



DISTINGUISHING CHARACTERISTICS The Sweet Gum, also known as Bilsted, Red Gum, 

 and Liquidambar, can be recognized by its fruit which is in the form of a spine-like heiad 

 suspended ou a long slender stalk. The fruit often persists far into winter. The corky-winged 

 projections on the bark of the branchlets are also characteristic. The Bur Oak, a native species, 

 and the Cork Elm, an introduced species, also have this characteristic. The star-shaped leaves, 

 reddish-brown twigs, aud leaf-scars with their bundle-scars are distinctive. It is native only 

 to the extreme southeastern part of the State, but rather commonly planted in other parts. 



RANGE Southern Connecticut south to Florida and west to Ohio, Missouri, and Texas, and 

 southward to Guatemala. 



DISTRIBUTION IN PENNSYLVANIA Found only in the extreme southeastern part of the 

 State. Reported from Bucks, Philadelphia, and Delaware counties. 



HABITAT It prefers deep rich soil such as will produce White Oak, Hickory, and Yellow 

 Poplar. Does not tolerate shade, hence almost invariably found in the open or in even-aged 

 stands. On account of its intolerance one seldom finds it as regeneration on the forest floor. 



IMPORTANCE OF THE SPECIES This species attains a large size and produces fairly valuable 

 wood but it usually requires soil adapted to agriculture or which will grow more valuable trees 

 such as White Oak, White Ash, Hickory, and Yellow Poplar. It hardly pays to propagate this 

 species artificially in this State and it is too limited in its distribution to regenerate it by 

 natural means. It is a very attractive ornamental tree. 



