SUGAR 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 accessibility 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 susceptibility 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 ina 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 account 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 
crown 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. While 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 younger trees for a second cut in from 50 to 60 years. It is 
expected that lumber prices will have increased by that time to a 
point which will allow of operating at a profit for a smaller per acre 
yield. ) 
Practical considerations demand that trees so situated as to be a 
hindrance to carrying out the most feasible and economical logging 
plan be cut whether mature or not. This practice is followed in 
preference to leaving such trees to inevitable injury, which will lessen 
their growth and perhaps cause disease. 
