PROTECTION OF THE WOODLOT 131 



The injury to the trees by surface fires can be shown imme- 

 diately after the fire by removing the outer bark. If the inner 

 bark looks brown or scorched the fire has killed the cambium 

 or growing layer at that point. A fire in a woodlot always 

 does great damage to the surface roots of trees. 



It is sometimes held that a fire is an advantage to a young 

 stand of growing timber, in that it will kill a few of the trees 

 and the rest will grow all the faster because of the greater 

 room in which to spread their crowns. A thinning is often 

 needed in a thick stand of young trees, but fire does not exer- 

 cise an intelligent choice as to the trees to be removed. The 

 trees killed are those most susceptible to damage by fire, as 

 those with thin bark or that contain a great amount of water. 

 It may happen that these trees are of the better kinds and that 

 those that will withstand fire the best are the poorest kinds 

 of trees in the woodlot. Fire passing through the woodlot 

 will often in this way bring about a change in the species 

 and cause the woodlot to deteriorate in character. 



It is in the destruction of the young seedlings and saplings 

 and of the seeds lying in the humus ready to germinate that 

 the greatest injury is done to the farm woodlot. The woodlot 

 can get along without the older trees. It is natural for them 

 finally through old age or disease to die and fall to the ground. 

 But a woodlot cannot get along without the younger trees. 

 As has been said, these are the children of the woodlot, and 

 if they are continually killed off by fire or other causes there 

 can be no future to the life of the woodlot. 



Fire passing repeatedly over the ground destroys the humus 

 and breaks down the crumbly character of the soil, making it 

 hard, much like a pavement. This prevents the circulation 

 of the air in the soil, which is necessary for root develop- 

 ment. It tends to prevent the entrance of moisture, the water 

 running over the surface instead of sinking into the ground. 

 It prevents the new tender roots that start from germinating 

 seeds from entering the soil, and so prevents the reproduction 



