BALSAM FIR. 



63 



upward, without breaking into the older stands. Logging from the 

 leeward side also permits the seed to be carried by the wind from the 

 mature stands to the logged-over area. 



Successive strips. — No matter how narrow the strips are made, 

 they should not be cut one after another every year, unless there is 

 sufficient young growth to insure a full stand. Spruce and balsam 

 do not bear seed every year, but at intervals of from four to six years. 

 If the strips are cut one after another every year, the logged areas 

 could not be reproduced for lack of seed. The stand adjoining 

 the logged area should be cut only after the latter has been fully 

 reseeded, or at the end of four to six years. With this method of 

 cutting the logging will have to be scattered over a fairly wide 

 territory. 



Alternate strips. — To avoid too great a scattering of the cuttings, 

 which necessarily increase the cost of logging, the strips may be cut 



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7 



81 



80 



79 



78 



77 



76 



Fig. 7. — Cutting in alternate strips. During the first half of the rotation only alternate strips are cut. 

 The remaining strips are cut over during the second half of the rotation. At the time the remaining 

 strips are cut the first strips are 75 years old and are capable of reseeding the adjoining clearings. 



alternately instead of one after another, at an interval of from 

 four to six years. In applying this method, the entire tract is divided 

 into strips narrow enough to insure natural reproduction. The 

 tract is cut over twice. The first time only alternate strips are cut; 

 the second time, the remaining strips. Every year as many strips 

 may be cut as are needed to secure the desired amount of timber. 

 Under this method the timber tract, after it has been entirely cut 

 over, would consist of strips of timber in which two adjoining strips 

 would differ in age by as many years as it took to cut over all of the 

 alternate strips. If 150 years is decided upon as the rotation for a 

 mixed stand of spruce and balsam fir, the entire tract would be cut 

 over in 150 years, and the alternate strips would be cut over within 

 the first 75 years. The strips that were cut first would then be 75 

 years old when the adjoining strips are cut. At the age of 75 years 

 both spruce and balsam bear seed prolifically, and will readily reseed 

 the adjacent clearings made by cutting the remaining strips (fig. 7). 

 Cutting in alternate strips tends to concentrate logging, since as 

 much timber may be cut per acre as under the present methods of 



