SPRUCE. 153 



larger than those of P. engelmanni. A large tree of strictly 

 conical growth and spreading branches. The seedlings vary 

 greatly in color from a bright glaucous blue to dark green. 

 The form having light colored foliage has become known as 

 Picea puny ens ylauca. 



Distribution. Valley of the Wind River south through the 

 mountain ranges of Wyoming, Colorado and Utah. 



Propagation. The species by seeds and the varieties by 

 grafting on the same or other species. 



Properties of wood. Soft, weak, light, close grained, satiny; 

 color very light brown or often nearly white: sapwood hardly 

 distinguishable. Specific gravity 0.374; weight of a cubic 

 foot 23.3 pounds. 



Uses. The Colorado Blue Spruce is a handsome orna- 

 mental tree that is now very popular with tree planters in this 

 section and elsewhere in the northern states. It is very orna- 

 mental when young, but its later development is often not so 

 pretty and if not growing rapidly when older it has a rather 

 ragged appearance; of slower growth than the White or Nor- 

 way Spruce, very hardy and well worthy of trial in a small 

 way. The wood is used within its range for fuel and timber, 

 although it is no where very abundant. A hedge of this tree 

 may be grown so close that even a dog cannot get through as 

 the sharp pointed leaves are exceedingly pungent, whence its 

 name. 



Picea engelmanni. Engelmaii Spruce. Rocky 

 Mountain White Spruce. 



Leaves t to 1 inch long, pointed but not as prickly as P. 

 pungens; branchlets pubescent. Cones solitary, l|to 2 inches 

 long; scales rhombic, the upper ends appearing as though 

 broken off; seeds smaller than those of P. pungens. In 

 form and color of foliage this species resembles P. pungens 

 but makes a larger tree often growing 100 feet in height. 

 In some nurseries it is customary to tell the Colorado Blue 

 Spruce from the Engelmann Spruce by grasping the top of 

 the young tree with the hand when if it pricks only a little, 

 the tree is set down as Engelmann Spruce, while if the 

 pricking is unendurable it is called Colorado Blue Spruce. 

 This method of determining the species generally gives 



