KEGlH^ATiON !N SULRC'i'ION l6l 



silviculture as market permits. With the selection method to fol- 

 low, it is quite immaterial where the cut begins, whether in one or 

 several places, and what its rate of progress at any point. wSimilarly 

 it is permissible to ignore conditions of types and future Working 

 Sections as well as a division into Cutting Series. 



In a property of this kind simple Regulation by Volume will 

 answer. If Von Mantel's formula is used and rotation is set at 120 

 years and period of return at twenty years the formula as in the 

 above case provides a cut of about 30% of the growing stock on 

 every acre cut over. For example: rotation 120 years; period of 

 return, twenty years; growing stock forty-five cords per acre, all 

 told ; area of forest 10,000 acres. 



The formula : 



Yearly Cut =G2/r = 2 X 10,000 X 45/120 ==■■ 7500 cords per 

 year. 



But since the plan calls for a return every twenty years, this 

 7500 cords is cut from 1/20 of the area or from about 500 acres. In 

 this way Regulation though really by volume, at once involves an 

 area consideration and takes the form of a combined method, just 

 as in the above case where regulation started with fixed yearly cut, 

 and merely used X'olume as a check. 



If in the foregoing plan a definite period of return is left 

 out, regulation of the cut merely prescribes that it take 7500 cords 

 and does not specify that this come' from 500 acres, but permits that 

 a heavier or a lighter cut per acre be made. While in this form it 

 becomes strictly volume regulation, yet in actual practice the plan 

 of silviculture also sets its limitations and if the forest is fairly 

 uniform, the forster naturally cuts different tracts in about the same 

 way, and covers nearly the .same area each year. But this again 

 leads to a more or less uniform period of return and with this to a 

 combination of Volume Regulation and Area Regulation. 



With a forest of hardwoods and ?Iemlock on good sites, as is 

 here considered, the question arises : should not this good site be 

 cleared at once and some more profitable species replace the hard- 

 woods? No doubt this is true. But to the owner of 10,000 or 

 20,000 acres this would mean quite a sacrifice in growth and in 

 valuable young growing stock. A much better way for the owner 

 who wishes to transform this \\ ild Woods into a paying forest 



