18 



CIRCULAR 791, U. S. DEPARTMENT OF AGRICULTURE 



The essentially even-aged character of the overstory in stands that 

 originated after fires often is obscured by later reproduction which 

 intensified the density of stocking in lightly stocked areas and filled in 

 unstocked spots. 



Despite the ability of black spruce to regenerate when seed-bearing 

 stands are burned, it does not reproduce after slash fires in clear-cut 

 areas because the seed on the ground and in cones in the slash piles is 

 consumed (fig. 12). 



The Effect of Logging Practices 



The method commonly employed in cutting spruce for pulp wood has 

 considerable influence upon spruce regeneration in swamps. Although 

 some new mechanical logging devices are now undergoing trial and 

 development, the ordinary method differs little in essential principles 

 from that used by pulpwood cutters 40 or 50 j^ears ago. 



The unit working area is the cutter's "strip," which is 60 to 80 feet 

 in width and several hundred feet in length. The pulpwood cutter 

 fells the merchantable trees within the strip, trims them, saws them 

 into 100-inch bolts. 13 The bolts are then carried by hand to an 8- to 

 10-foot wide skid road that is cut through the center of the strip. The 

 cutter clears the skid road as cutting progresses. 



In order to keep effort to the minimum, the cutter fells the trees 

 in directions that will (1) minimize carrying of the bolts and (2) 

 avoid throwing tops and limbs into the cleared skid road. As a 

 result, the tops and limbs accumulate in rather regular windrows 20 

 to 30 feet in width and up to 6 feet in depth along both sides of the 

 skid road (fig. 13). 



MP&& " 



'*&4W 



F-400363 



Figure 13. — Clear-cutting operation in a black spruce swamp. The logging 

 debris — tops, limbs, and bark — make much of the ground surface unfavorable 

 for reseeding. 



13 Some mills require 96-inch bolts, one mill 50-inch bolts. 



