CONTBOL OF GIPSY MOTH BY FOREST MANAGEMENT. 7 



quantity of the white pine is suitable only for box boards, and a 

 large portion, possibly 75 per cent, of the deciduous growth is suit- 

 able only for fuel. 



The composition and physical condition of woods subject to gipsy- 

 moth infestation have a very important bearing on the extent of the 

 damage which may ensue therefrom. Coniferous trees grown in 

 pure stands are immune from any considerable damage. The ashes 

 are seldom attacked, and the red maple, sugar maple, hickories, and 

 chestnut are not seriously affected. The proportions of such species 

 occurring in stands have considerable influence upon the degree of 

 damage done. Trees weakened by drought, fungi, fire, suppression, 

 or other unfavorable growing conditions can offer only a weak 

 resistance to the effects of defoliation and so are much more likely 

 to succumb than vigorous trees. 



The presence of dying and weakened trees in a wood is very objec- 

 tionable, inasmuch as such trees harbor injurious borers, and these 

 multiply rapidly when favorable conditions for their entrance into 

 other trees are provided by defoliation. 



The forests of the infested region are highly valued for their at- 

 tractiveness and the protection they afford. There is probably no 

 region in which the esthetic features of woods are more valued than 

 in New England, and there are numerous instances where they are 

 maintained largely out of consideration for their appearance. Woods 

 thus maintained are generally of better quality than others, but there 

 is usually a chance to increase the commercial value of many such 

 stands. Such improvement would not impair esthetic values. 



It is quite impossible to appraise the damage inflicted upon owners 

 of woods by gipsy moths. The woods vary so much in composition 

 and quality, and individual trees suffer in such varying degree, that 

 there is no available basis for such an estimate. The esthetic value 

 which an owner or community places upon woods adds to the diffi- 

 culty of such an appraisal. Individuals and communities have fre- 

 quently gone to large expense to protect inferior stands of timber 

 against the ravages of the gipsy moth, and in such cases the reduction 

 of infestations is of greater importance than the conservation of the 

 woods alone, since adjoining fruit and shade trees are thereby pro- 

 tected. 



The scarcity and corresponding values of forest products of good 

 quality in New England appear to justify an outlay in improvement 

 measures. Trees capable of producing only material of low value 

 should be removed and replaced by more valuable species. Defective 

 and dying individuals should be made to give way to vigorous trees. 

 Trees growing on sites on which other species will yield greater values 

 should be replaced by such species. The complexity of many stands 



