320 



TREES OF NORTH AMERICA 



thick, smooth, dark brown, and more or less thickly covered and roughened by irregular 

 wart-like excrescences or by long ridges also found on the large branches. Wood heavy, 

 rather soft, not strong, coarse-grained, clear light yellow, with thick lighter-colored sap- 

 wood; used for fencing and in the manufacture of cheap furniture. 



Distribution. Rocky hills and ridges; New England (rare) to Virginia and westward 

 to Iowa, eastern North Dakota, southwestern Missouri and northwestern Kansas. 



Often planted in some of its forms as a shade and ornamental tree in the towns of the 

 Mississippi valley and occasionally in the eastern states and in Europe. 



Well distinguished by its large dark fruit, Celtis occidentalis is so variable in the shape of 

 its leaves that two principal varieties are described as follows: 



Celtis occidentalis var. canina Sarg. Hackberry. 

 Celtis canina Raf . 



Leaves oblong-ovate, gradually narrowed into a long acuminate point, obliquely rounded 

 or unsymmetrically cuneate at base, finely serrate, glabrous or rarely pilose along the 

 midrib and veins below, 2|'-6' long and f-2^' wide; petioles slender, glabrous or rarely 

 pubescent, !' |' long. 



A tree, often 80-100 high; more common than the other forms of Celtis occidentalis. 



Distribution. Rich wooded slopes and bottoms, or eastward on rocky ridges; Province 

 of Quebec to eastern Nebraska, and southward to the coast of Massachusetts, western 

 New York, southern Ohio, southern Indiana and Illinois, southwestern Missouri, south- 

 western Oklahoma (Snyder, Kiowa County), and in northwestern Georgia. 



Celtis occidentalis var. crassifolia A. Gray. Hackberry. 



Celtis crassifolia Lam. 



Leaves thicker, long-acuminate, obliquely rounded at base, usually more coarsely ser- 

 rate, rarely nearly entire, rough on the upper surface, pilose below along the prominent 

 midrib and veins, 3|'-5' long, 2'-2|' wide, much smaller in the Rocky Mountain region; 

 petioles villose-pubescent, rarely glabrous, \'-% in length, much shorter than the pubescent 

 pedicels of the fruit. 



A tree, 100-120 high; with pubescent or glabrous branchlets; rarely shrubby. The 

 most widely distributed form of Celtis occidentalis. 



Distribution. Wooded slopes and rich bottoms; Virginia and along the Appalachian 

 Mountains to North Carolina and westward to southern Minnesota, Missouri, central 



