n6 Forests and Trees 



the forest marched northward. The order and procedure 

 is true, not only of the eastern forest where the merging of 

 the conifers and hardwoods is complete, but also of the 

 prairie region where the hardwood belt is replaced by open 

 plain. It is approximately true also of the mountain 

 section, except that the factor of altitude operates more 

 strongly. Elevation produces much the same result as 

 higher latitude, and the conifer forest persists, relieved to 

 a large extent by physical conditions from the struggle 

 with the broad-leaved trees. And who is going to say 

 that the forest is not still moving northward ? The barren 

 lands of the north are barren, not so much because they are 

 so far north, as because that is a stage through which forests 

 pass. These lands may yet furnish their full share of our 

 national wealth. 



