SILVICULTURAL MANAGEMENT OF BLACK SPRUCE IN MINNESOTA 7 



of little commercial importance. It is relatively much more abundant 

 in the northern portions of Wisconsin, Michigan, and particularly 

 Minnesota. 



The natural distribution of black spruce in Minnesota is rather 

 well depicted by figure 6, which shows the original coniferous swamp 

 forests. Black spruce was the- principal tree species in the majority 

 of these swamps. Of course, some of the swamps were stocked with 

 tamarack (Larix laricina), some with northern white-cedar (Thuja 

 occidentalis), or with various mixtures of black spruce, tamarack, 

 white-cedar, and balsam fir. Black spruce probably did not extend 

 quite to the extreme southern and western outposts as shown on the 

 map. 



L. 



Figure 6. — Original coniferous swamp forests in Minnesota. Forest Survey 

 units: (1) Cloquet, (2) Central Pine, (3) Rainy River, (4) Superior, (5) 

 Central Hardwood, (6) Prairie. (From a map compiled from General Land 

 Office field notes by F. J. Marschner, Bureau of Agricultural Economics, U. S. 

 Department of Agriculture. ) 



