THE SPECIES. 



45 



The Douglas spruce has been planted in the Eastern States and 

 cultivated largely in Europe. Its wood is of great importance in 

 heavy construction, for ship building, for masts and spars, for inte- 

 rior finish, and a great variety of uses. 



FIRS. 



Most of the true firs are large forest trees. They are natives of the 

 cooler regions and are partial to moist soils. For these reasons they 



FIG. 2: 



olranci Fir. .1, Twig and cone in natural position; B, bract and lower side of 

 seed-bearing scale ; C, seed. 



are found in northern latitudes and the higher elevations of moun- 

 tains and reach their bost development on river bottoms, in canyons, 

 and on mountain slopes close to perennial snows. Many of them are 

 shade-enduring species and grow for years in the shelter of thickets. 

 Under favorable conditions they grow rapidly, reproduce plentifully, 

 and are widely distributed, sometimes in pure, sometimes in mixed 

 stands. 



The distinctive marks of the firs are usually recognized with ease. 

 The leaves are flat, blunt at the apex, and somewhat narrowed at 

 the base. They arise equally from all sides of the twig in alternate 



