78 



THE SPRUCES— PICEA, Link. 



The Spruces are evergreen trees with stiff, often sharp-pointed 

 needles which persist for 7-10 years. All the species of Spruce found 

 in eastern North America and all but two species found in western 

 North America have four-sided needles. The tw'o exceptions have 

 flattened needles and bear stomata, commonly knoTSTi as breathing 

 pores, only on the upper surface, while the species with four-sided 

 needles have stomata on all sides. The needles are spirally ar- 

 ranged on the branches and are not stalked but borne on decurrent 

 projections of the bark known as sterigmata. The staminate and 

 pistillate flowers are separate on the same tree, usually on the same 

 branch. The staminate, which bear the pollen, are yellow to red 

 in color, cylindrical in outline, and open lengthwise. The pistillate, 

 which develop into cones, are erect, cylindrical, short-stalked, and 

 pale yellow to scarlet in color. The cones mature at the end of one 

 season and are always drooping and usually cylindrical to ovate in 

 outline. The cones usually fall entire during the first winter or 

 sometimes persist for a few years. They consist of numerous per- 

 sistent cone-scales which are thin and unarmed, and consequently 

 stand in strong contrast ^^ith the thick, usually armed, cone-scales 

 of the Pines. The cone-scales are largest near the center and de- 

 crease in size towards the apex and the base. The fertile scales bear 

 two winged seeds on each cone-scale. The seeds are usually light 

 and bear a rather large wing, by means of which they are dissemi- 

 nated over great distances by the wind. 



The trunks of the Spruces are straight, continuous, and taper 

 gradually to the top. The lumbermen for -a long time looked un- 

 favorably upon the Spruces but owing to changed economic condi- 

 tions and a more thorough knowledge of their technical value, these 

 same species are now' considered among our most important com- 

 mercial .species. The wood of these same species is now considered 

 amongst the most important of the northern hemisphere and espec- 

 ially adapted for the manufacture of paper pulp. The spruce for- 

 ests of North America for a long time remained practically un- 

 touched, but are now being exploited on a gigantic scale. The 

 march of forest destruction is very rapid since an enormous supply 

 is required for the paper pulp industry. In order to supply this 

 growing demand and not dimini.sh the available supply of spruce 

 wood it is necessary that proper and systematic treatment be given 

 to the existing spruce areas, since we cannot hope to import a supply 

 suflBcient to satisfy our demand. 



