SI 'RUCK. 221 



Picea parryana. (/'. />/^/,^YV/.S.) Colorado Blue Spruce. 



Silver Spruce. White Spruce. Blue Spruce. 



Leaves about one inch long, rather broad, rigid, stout, 

 pointed, usually incurved, falling during sixth and seventh years; 

 branchlets smooth and shining. Cones light brown in color, 

 very prickly, three to five inches long, cylindrical, with more or 

 less elongated thin truncate wavy scales; seeds small but larger 

 than those of P. cngelmanni. 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 hav- 

 ing light colored foliage has become known as Picea pungens 

 glanca. 



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 graft- 

 ing 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 ornamental 

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

 and elsewhere in the Northern States. It is very ornamental 

 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 Norway 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 nowhere 

 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. 



Picea engelmanni. Engelmann Spruce. Mountain 

 Spruce. White Spruce. 



Leaves three-quarters to one inch long, pointed, but not as 

 prickly as P. parrayana; branchlets pubescent. Cones solitary, 

 one and one-half to two inches long; scales rhombic, the upper 

 ends appearing as though broken off; seeds smaller than those of 

 P. parrayana. In form and color of foliage this species resembles 



