American Arbor-Vitae 



95 



Teijnessee. Its maximum height is 22 meters, with a trunk diameter of 1.6 meters. 

 Sometimes, however, it is only a shrub. 



The trunk is often fluted and much buttressed at the base, and frequently 

 divided into several smaller upright trunks. The branches are horizontal, short, 

 more or less curved upward toward the ends, forming a dense, narrow, cone- 

 shaped tree. The bark is about 6 mm. thick, shallowly fissured into long, narrow 

 ridges, which peel off into long fibrous persistent shreds of a Hght yellowish or 

 reddish brown color. The twigs are flattened, somewhat 4-sided, sometimes zig- 

 zag, light yellowish green, changing to hght reddish brown, and finally darker 

 brown, and become round and marked by the scars of the fallen lateral twigs, 

 which are pendulous and fall away after having become about i dm, long. The 

 leaves are yellowish green, scale-hke, ovate to lanceolate, 6 mm. long, sharply 

 pointed at the apex, and glandular on the back, on the larger twigs; on the lateral 

 twigs they are much smaller, scarcely glandular, the lateral rows much keeled, the 

 others flattened, giving the twigs a very flat appearance. The flowers, appearing 

 from April to June, are about 1.5 mm. long, 

 and pinkish. The cones ripen in the au- 

 tumn, and shed their seed, but persist dur- 

 ing the winter; they are oblong, 8 to 12 mm. 

 long. The scales are leathery, oblong, 

 blunt-pointed, or minutely tipped, the inner 

 having 2 seeds, the outer often but i seed 

 or none. The seeds are oblong, about 6 

 nmi. long; their wings about as wide as the 

 body, appearing notched at the apex. 



The wood is soft, brittle, rather coarse- 

 grained, hght yellowish brown, and fra- 

 grant; its specific gravity is about 0.32. It 

 is very durable, and is largely used at the 

 North for railroad ties, fence-posts, and 

 shingles. The sapwood is easily separated 

 into thin strips, which are used by the 

 Indians in their basketry, and is also made into brooms ; preparations of the green 

 twigs are used in medicine. 



As an ornamental plant it is well known in northern North America and in 

 Europe, especially used for hedges and cemetery ornamentation, and having been 

 long in cultivation, a great many forms have been developed that are now known 

 under many different names. 



Fig. 71. American Arbor-Vitae. 



