704 A NATIONAL PLAN FOR AMERICAN FORESTRY 



of timber that can be obtained from a given unit of area as determined 

 by estimate. If decay is underestimated in a highly defective stand, 

 the amount of timber obtained may be so much less than expected 

 that it is not possible to make a profit on the operation, since more 

 milling and logging equipment would be set up than the volume of 

 timber warrants. Again a knowledge of the outward indications of 

 decay makes possible more intelligent utilization of standing timber. 

 For example, in the Douglas fir region, it is now possible to judge the 

 amount of decay in individual trees with considerable accuracy, so 

 that felling and bucking charges on them are avoided. 



In forecasting losses from decay in timber stands of the future it is 

 reasonable to presume that utilization will not only be at earlier ages 

 than at present but that it will be closer. At current levels of value 

 and with lumber as the chief product a considerable amount of sound 

 wood adjacent to decay has to be sacrificed because its salvage can- 

 not be made to pay. There is reason to believe that in the future not 

 only will wood values increase to some extent but that a larger pro- 

 portion of the cut may go into cellulose, alcohol, or other derived 

 products in which closer utilization is possible. The loss in cull due 

 to decay may therefore be expected to be lower. 



In many species, decay commonly enters the tree through open 

 wounds, and the most common wounds are fire scars. Decay then 

 first destroys the wood in the basal part of the trunk, which is com- 

 monly the most valuable portion of the tree. In small trees the only 

 saw timber of satisfactory grade is often in the first 16-foot log. In 

 eastern hardwoods most decay, which frequently begins at an early 

 age, is directly connected with fire scars. Consequently in most 

 forest regions adequate fire protection is a valuable method of reducing 

 losses from decay. 



From the foregoing, it might be concluded that by sanitation in 

 connection with thinning and logging operations, by utilizing the 

 trees at younger ages and by improved methods, and by better con- 

 trol of fire, the disease losses in the forests of the future should be less 

 than in the virgin stands which have been our principal source of 

 forest products in the past. For two reasons it is impossible to take 

 this expectation at its face value. In the first place, the desirable 

 practices just mentioned are not being applied to most of our stands. 

 Only a small part of our forest area is really under management, and 

 under present economic conditions most of it cannot profitably be put 

 under any but the most superficial management. Much of our second 

 growth has been more fire scarred than was the virgin forest, and in 

 addition has been subjected to undue mechanical wounding during 

 the logging process. Instead of aiding in sanitation of forests, the 

 bulk of our logging operations have removed the best timber and left 

 the worst infected trees in the woods. In the second place, though 

 we call them natural forests the stands that are coming back on old 

 fields and cut-over land are developing under conditions that are in 

 many ways abnormal. While their health prospects are better than 

 for plantations, the soil conditions, stand density, and species mixture 

 may be quite different in young natural forests from those developed 

 under truly natural conditions. Whatever the reason, there appears 

 in some cases to be more disease damage in second growth than is 

 found in trees of the same age in virgin forest. It is probable that 

 future timber crops as a whole will suffer less cull because of heart 



