Figure 35. — Reserve stand after 40 percent cutting. Trees Jelled were high in quality and large 



F347937 



in size. 



In actually applying these rules to specific stands 

 many trees fall into one or another of these cate- 

 gories without question, but conflicts also occur. 

 For example, what shall be done with low-quality 

 trees of low-value increment, high-quality trees of 

 high-value increment, and low-quality trees of 

 high-mortality probability? Many other conflicts 

 occur in practice. It is not always possible to 

 eliminate all highly insect-susceptible trees through 

 logging and still cut lightly enough to avoid accel- 

 erated windfall losses. 



The Maturity-Selection Sysltm 



Recent studies by Brandstrom (2) on the eco- 

 nomics of ponderosa pine management have 

 demonstrated the advantages of a light initial cut 

 on areas being managed for sustained yield. 

 These studies resulted in the development of the 

 so-called maturity-selection system based on the 

 removal of the high-value overripe trees that are 

 generally the least productive in the stand both 

 economically and silviculturally. This system 

 results in a first cut far below past practice, in one 



instance as low as 40 percent (fig. 35). Excep- 

 tions from the basic rule allow cutting of certain 

 low-value trees of poor vigor and leaving high- 

 value trees of above-average vigor. Generally 

 there is close correlation between silvicultural and 

 economic objectives under this system, and re- 

 moval of the high-value trees converts the stag- 

 nant forest to a growing condition. Under this 

 light cut it is unnecessary to dispose of slash except 

 in certain vulnerable locations, thereby so improv- 

 ing soil conditions as eventually to increase the 

 productive capacity of the forest site. 



Region-wide application of such a system would 

 greatly facilitate and hasten sustained-yield man- 

 agement, thus stabilizing industries and communi- 

 ties. As already demonstrated in the chapter on 

 forest growth, light selection will increase regional 

 growth at a faster rate than heavy selection. The 

 more rapid spread of logging over the entire region 

 will result in the development of an extensive net- 

 work of roads which will assist in fire control and 

 make more feasible salvage of insect-killed, fire- 

 killed, and wind-thrown timber. Furthermore, 



70 



