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The destruction of stored hickory, oak, maple, and other hardwood 

 lumber, and the various products manufactured from hard woods, due 

 to the ravages of powder-post beetles {Lyctus spp.), is a widespread 

 trouble in this and other countries, and has caused the loss of a vast 

 amount of valuable material. Yet comparatively little has been done 

 in this country toward a detailed study of the problem and the 

 elaborate experiments necessary to determine methods of preventing 

 attack. 



THE INTEKKELATIONS OF INSECTS, FUNGI, AND FIKES IN THE DESTRUC- 

 TION OF FORESTS. 



This is another problem that recent investigations have demon- 

 strated is one of very great importance. Heretofore it has been 

 almost entirely overlooked, and much of the destruction which has 

 been going on in all of the great forest areas of the country that is 

 primarily due to insect attack, and secondarily to fungi, has been 

 attributed to forest fires, which really occupied third place among the 

 destructive factors. 



The examples of destructive insect ravages mentioned here are only 

 a few of a long list that could be given. They should be sufiicient, 

 however, to indicate the number and the magnitude of the problems 

 in forest entomology, which, on account of their special economic 

 importance, should be thoroughly investigated. 



The need of exhaustive study of these problems is all the more 

 apparent when it ia realized that comparatively nothing is known of 

 the more important facts relating to the life history and habits of 

 some of the principal depredators, the conditions that contribute to 

 sudden and destructive invasions, or those that bring about an equally 

 sudden ending of a serious trouble. Without this knowledge little or 

 nothing can be done toward the recommendation of effectual methods 

 of preventing losses. Enough has been determined from a detailed 

 study of some of these problems to indicate quite clearly that a better 

 knowledge of some of the fundamental facts will lead to the adoption 

 of simple, inexpensive methods by which the loss of a vast amount of 

 timber and timber products may be easily prevented. 



REMEDIES AND OTHER METHODS OF PREVENTING LOSSES. 



The problem of controlling insect enemies of forests is quite a 

 diflferent one from that relating to the control of farm, garden, and 

 fruit and shade tree insects. Indeed, they must be considered from a 

 diflferent standpoint — that of prevention rather than that of destruction. 

 Thus every separate trouble caused by diflferent insects or the troubles 

 caused by the same kinds of insects in diflferent sections of the country 

 must be studied separately with a view to determining methods of 



