SUGAR PINE. 33 
nature the reproduction of the more light enduring species, such as 
yellow pine, white fir, and Douglas fir, take possession of the openings 
first, and young sugar pines are confined to the zone of partial shade 
around the groups left. Later, after partial shade has been estab- 
lished in the openings, some sugar pine enters the mixture and tends 
eventually to outdistance the other trees because of a more rapid and 
sustained rate of growth. This method of cutting is known as the 
group-selection system. Generally from 65 to 75 per cent of the 
board-measure content of the stand is removed. 
On areas covered with trees of various ages mingled together the 
so-called selection system of cutting must be applied. Each tree is 
subjected to the test of maturity, health, and value of contents. 
Mature and unhealthy trees are removed. Immature trees, or trees 
of the less valuable species, such as fir and cedar, are left to furnish 
shade and protection. Whenever it is necessary to remove a few 
pines not fully mature in order to make the operation profitable, those 
that will yield the highest grade product are selected. 
Such a cutting results in maximum openings of an acre in the forest 
cover and in theremoval of from 75 to 85 per cent of the mature stand. 
These openings will, it is believed, on fairly favorable situations 
restock with yellow pine, fir, and cedar, followed by sugar pine when 
proper shade conditions have been established, as in the group- 
selection system. : 
UTILIZATION. 
While logging on private lands is still wasteful, utilization is far 
more complete than it was 10 or 15 years ago. At that time only the 
larger pine trees were cut. Stumps were sometimes cut as high as 4 
feet and only the clear length of the trees removed. Wasteful lum- 
bering in the past has been due primarily to low stumpage values and 
poor market,conditions. The cost of transportation has been another 
important factor, since only the better class of material could be 
hauled to market at a profit. 
With the rapid growth of the lumber industry in California more 
modern methods of logging have been adopted. Some concerns cut 
only the best fir and cedar, but pines are frequently utilized to a 
diameter of 10 inches in the tops. Stumps are usually cut from 18 to 
24 inches high. Even tops and limbs are, in favorable localities, 
utilized for firewood. 
In sales of National Forest stumpage the closest utilization con- 
sistent with modern logging methods and market conditions is prac- 
ticed. Stumps are cut 18 inches or less in height; trees are utilized 
to a top diameter of at least 10 inches in the case of pines and 12 
inches for other species, and all species are logged. Pine logs which 
contain 33 per cent, and logs of other less valuable species which con- 
_ tain 50 per cent sound lumber, are considered merchantable. 
