CIRCULAR 791. U. S. DEPARTMENT OF AGRICULTURE 



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Figure 5. — Black spruce Christmas trees cut from a nearby low-sire swamp that 

 is incapable of producing pulpwood. This load contains several thousand small 

 ■'table trees" 30 indies in beigbt. They were cut under tbe supervision of the 

 Minnesota Forest Service from State-owned land. These Christmas trees are 

 top sections from trees about 20 feet in beigbt and SO years of age. 



Black spruce is able to grow also on upland soils where frequently 

 it forms one of the important components in variously mixed stands. 



The Lake State- Forest Experiment Station has been studying the 

 reproduction, growth, silvieultural requirements, and harvesting of 

 black spruce since 1932. The bulk of the experimental work has 

 been conducted within the Superior National Forest in northeastern 

 Minnesota but a considerable amount also has been carried out else- 

 where in northern Minnesota, particularly in Koochiching County 

 in cooperation with the Minnesota State Forest Service. These 

 studies are the basis for this report. 



RANGE AND OCCURRENCE 



Black spruce has an exceedingly wide natural range, being one of 

 the very few North American conifers that reaches from the Atlantic 

 Ocean to the Pacific Ocean. It occurs in Newfoundland and within 

 practically all of the forested portions of Canada, except the western 

 and southern parts of British Columbia and the southern part of 

 Alberta I 27). Only a small fraction of the natural range lies within 

 the United States. In the eastern States, where black spruce extends 

 as far south as West Virginia in the Appalachian Mountains, it is 



