THE SPRUCE REGION 



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The type is found all through the region, being most abundant 

 in sections where there have been many and large burns in 

 previous years. Within the last ten years better fire protection 

 has been the rule. This prevents the formation of seed-bed 

 conditions favorable to the start of birch and poplar stands. 



Fig. 72. — Birch and poplar type. A 40 year old stand on an old burn, chiefly yellow 

 birch and pin cheixy. Beneath the hardwoods conifers are coming in. 



Thus the area of that type cannot be increasing. Instead of 

 being stationary it is decreasing, because reversion to other types 

 is continually lessening the present area. 



The birch and poplar type is an example of an even-aged 

 forest. The majority of the trees in a given stand started at 

 practically the same time and are more nearly of the same 



