Conservation Commission 137 



true that large trees are seldom consumed by any except crown 

 fires, great numbers of trees are killed by having their roots 

 burned and the soil which supports them destroyed by severe 

 ground fires. These fires so weaken the roots of the trees that 

 they fail to give sufficient support and at the first sign of heavy 

 wind, the tree topples over. In the dense forests of the Adiron- 

 dack region and in certain other parts of the State, there is prac- 

 tically no mineral soil covering the bed rock. In these cases a 

 severe ground fire burns away the accumulation of ground litter, 

 humus, or so-called " muck," which constitutes the soil, until 

 there is nothing left to sustain the tree. 



Ground fires are extremely destructive in killing young growth 

 or reproduction, that is, the stand of saplings and seedlings which 

 are to form the body of the future forest crop. The smaller trees 

 are either entirely consumed, or at least killed, by a ground fire. 

 Even a surface fire may so weaken their powers of resistance, that 

 they will succumb within a short time. 



Indirect Damage 



This brings us to a consideration of the question of injury which 

 is indirectly due to forest fires. It is a well recognized fact that 

 when trees have been weakened by any cause, they are more liable 

 to suffer from the attacks of insects or of disease germs than when 

 they are growing thriftily. Forest fires, in burning over an area, 

 leave bad fire scars on the trunks of many trees which are not actu- 

 ally consumed. These scars permit the ingress of fungi and in- 

 sects, which injure and frequently destroy the tree. Damage done 

 to timber by fungi which have secured ingress through fire scars 

 at the base of the tree is exceedingly hard to appraise, especially 

 in hardwood timber. New growth may cover the scar completely, 

 leaving little or no indication on the surface of the defects within. 

 Tree species vary widely in their power of resistance to fire, and 

 this variance must be studied if one would hope to understand the 

 degree of damage suffered by the forest. 



Another form of indirect damage due to fire is the destruction 

 of the proper relationship between the number of trees and the 

 area upon which they stand, namely, in the reduction of the den- 

 sity of the stand, which is consequent upon the elimination o^ the 



