SUGAE PINE. 31 



The exact age at which sugar pine and the various species which 

 enter into combination with it should be cut to yield the highest 

 return is dependent upon so many variable factors that it is impos- 

 sible to determine it with accuracy at present. Even if this were 

 determinable, however, such a cutting age (rotation) could not be 

 strictly adhered to, because, under present economic conditions, 

 demand and accessibihty must largely determine the time and place 

 of cutting. We know, however, that stands of yellow pine and sugar 

 pine reach their highest rate of volume production at about 180 years. 

 On average sites the diameter of sugar pine is approximately 33 inches, 

 and of yellow pine 30 inches at this age. White fir and cedar, the 

 two other principal species in mixture, while not so large at this age, 

 are of merchantable size and usually in need of cutting on account 

 of their susceptibihty to disease. Therefore, without danger of serious 

 error, stands in which sugar pine is an important tree may be cut 

 down to a diameter of about 30 inches. 



This principle is used as a guide in the cutting done in such stands 

 within the National Forests, although the removal of smaller trees 

 and the leaving of larger is practiced whenever necessary for a 

 weighty special reason, such as the elimination of disease or the 

 creation of conditions favorable to reproduction. Diseased trees 

 are always cut and the merchantable portions utilized, since sani- 

 tation is as essential to health in a forest as in a human community. 

 Dead trees are a source of danger in time of fire and are felled. The 

 cost of this work to operators — ^generally from 3 to 7 cents per 1,000 

 feet — is taken into accomit in fixing the stumpage rate. 



Timber apparently ripe is always harvested, except when it is 

 clear that reproduction can not be secured on the area unless a few 

 trees of this class are left for seed or shade. The condition of the 

 cro"wii of the tree determines which individuals are to be cut. Trees 

 whose crowns are flattened are mature, or are not making profitable 

 growth, and should be removed. It is recognized that sufficient 

 timber must be secured from each tract to make the operation 

 profitable. Wliile this amount varies with the investment and with 

 logging conditions, from 12,000 to 18,000 feet per acre is usually a 

 profitable cut. The removal of this amount should leave a sufficient 

 basis of yoimger trees for a second cut in from 50 to 60 years. It is 

 expected that lumber prices wiU have increased by that time to a 

 point whi(;h will allow of operating at a profit for a smaller per acre 

 yield. 



Practical considerations demand that trees so situated as to bo a 

 hindranf-e to carrying out the most feasi})le and economical logging 

 plan bo cut whether mature or not. This practice is followed in 

 preference to leaving such trees to inevitable injury, which will lessen 

 tlicir growth mikI perhaps cause disease. 



