136 FOREST VALUATION 



it will be difficult to estimate accurately the probable loss on a 

 new crop, unless the effect of similar burns can be cited. 



The cost of restoring soil value by removal of debris ( 142, 2 ) 

 is wholly apart from the appraisal of physical damage to the 

 soil itself. Except in unusual cases, this physical damage is 

 exceedingly difficult to measure in terms of value, and, where 

 timber is destroyed, destruction of soil represents but a small 

 proportion of the total loss. This item of damage is, therefore, 

 neglected in most instances. 



144. Damage to Single Trees. When the expectation 

 value of young timber is made the basis of damages, and the 

 present value of future crops is calculated, the future expenses 

 deducted from value are based on the acreage protected and 

 utilized by the crop. The yield of the timber is also computed 

 on the basis of area, and in this way the normal loss in numbers 

 which occurs in all stands with increasing age is allowed for. 



In scattered stands of timber, the individual tree becomes 

 more important, and this importance increases in stands com- 

 posed of trees of many ages. Damage or loss in such forests 

 cannot as easily be appraised as for crops of even-aged trees. 

 The mature timber can be estimated according to its merchant- 

 able contents. If these trees are still small, though merchant- 

 able, it may be possible to show that their future increase in 

 volume and quality, with consequent increase in value, is such 

 that this discounted value exceeds the present value of the 

 trees. 



If it be assumed that all trees now merchantable will remain 

 standing, and future expenses are neglected, the expectation 

 value so obtained will be too high. Such figures must be reduced : 



By allowing for loss of numbers; 



By pro-rating the crop expenses among the reduced stand, per 

 tree, according to present volume. 



The immature portion of such stands cannot, with any degree 

 of accuracy, be valued on the basis of individual trees. The loss 

 in numbers previous to maturity increases with decreasing age, 

 and the proportional expense to be charged to each tree becomes 

 wholly problematical. 



