CONIFEES OF THE ROCKY MOUNTAIN EEGION. 37 



T'als by thinner diagonal ridges and fibers. In texture and appear- 

 mce the bark is more or less stringy and fibrous, so that in the case 

 )f young trees it may be separable into long, thin strips, while in 

 he case of old trees the bark is separable only into shorter scales, 

 rhe inner bark is very tough and strong, particularly that of young 

 Tees, from which Indians peel strips of bark 20 or 30 feet long for 

 casket making. 



The small scalehke leaves (Pis. XI, XII), the arrangement of which 

 s described under the "Generic Characteristics of Arborvitaes," 

 :'emain on the trees about 3 years. Leaves of vigorous leading 

 shoots usually have a tiny gland on the back side, while the leaves of 

 ihe more slowly grown lateral twigs are marked on the back by a 

 small pitlike depression. As the main stems of a branch grow, 

 bheir short, flat, side branchlets die and fall during their second 

 ^ear, as is the case also with similar sprays of Libocednis. The 

 Leathery-brown cones (PL XI), which mature by the end of August, 

 tiave about 6 seed-bearing scales, each of these producing from 2 to 

 5 seeds. After shedding their light double-winged seeds (PL XI, a) 

 the cones remain on the trees until the following spring or summer, 

 rhe seed-leaves, 2 in number, are opposite, lance-shaped, and about 

 [)ne-fourth of an inch long (PL XI, h — lowermost pair). The primary 

 [eaves, those that succeed the seed-leaves, are similar to the latter 

 in form, and like them also they are widely spread and more or less 

 bent downward. The stiJl shorter, spreading, sharp-pointed, scale- 

 like leaves produced next are somewhat similar in form to those on 

 adult trees, and appear at the end of the first or second year's 

 growth. Leaves produced a year or two later are like those of adult 

 trees. 



The wood of western red cedar is very soft and brittle, and has a 

 strongly aromatic odor. It is the lightest in weight of all the 

 coniferous woods in the Rocky Mountain region, a cubic foot of 

 seasoned wood weighing only about 23^ pounds. When freshly cut, 

 the thin layer of sapwood is whitish and the heartwood is a dull, 

 shghtly reddish brown, this tinge being lost by gradual exposure 

 to the fight, and replaced by a yellowish brown. The annual layers 

 of growth vary in thickness from moderately wide to narrow. The 

 straight grain of this wood renders it easy to spfit and its soft texture 

 makes it one of the easiest to work. Great durability under all 

 sorts of exposure is one of its most important commercial qualities. 

 Large logs have lain half buried in wet ground for over 50 years 

 with but little decay of the heartwood. On account of its durability 

 and the large clear cuts obtainable, western red cedar is very exten- 

 sively used for shingles, as well as for other commercial purposes 

 requiring large dimension pieces. It is also much used in combina- 

 tion with Douglas fir in the manufacture of doors. Young timber 



