- . - SUGAR PIXE. 33 



nature tile reproduction of the more light enduring species, such as 

 yellow pine, white fir, and Douglas fir, take possession of the openings 

 fii'st, 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 

 eTentuaUy 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 the removal 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 adoj)ted. Some concerns cut 

 only the best fir and cedar, but pines are frequently utilized to a 

 diameter of ] 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 marlvet conditions is prac- 

 ticed. Stumps are cut 18 inches or less in height; trees arc utilized 

 to a top diameter of at least H) in(;hcs in the case of pines and 12 

 inrhcs 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 ])cr cent sound lunil;cr, are considered jnerchantablo. 



