168 NEW YORK STATE MUSEUM 



of 1900 and the following many of the borers emerged from these 

 dying trees and entered others, in which latter they were 

 presumably the prime cause of death. The evidence at hand 

 leads us to believe that in this case the bark beetles were primarily 

 attracted to certain trees because of reduced vitality, possibly as 

 a result of the excessive drouth of the preceding year, and that all 

 subsequent injuries were due to their abnormal abundance ; since 

 they issued from the infested trees in swarms and attacked th'ose 

 adjacent, and the insects breeding from the latter in turn invaded 

 others more remote from the center of infestation. The obtaining 

 of data along these lines is somewhat difficult, since it is dependent 

 on favorable conditions, and the following account of observations 

 made during the past season has an important bearing on one 

 aspect of this subject. 



Forest fires and insect attack. The annals of entomology contain 

 very little regarding the relationship existing between forest fires 

 and insect attack, and the extended burnings last spring in the 

 Adirondacks, presented a most favorable opportunity for studying 

 this question, so far as fires occurring at that time of year are con- 

 cerned. The principal object was first to secure data on the 

 rapidity with which insect injury followed fire, and second to 

 learn if there was a connection between extended fires and serious 

 damage by insects in adjacent forests. It is very probable that 

 the time of year when the fire occurs, has considerable bearing on 

 the liability of insects entering the trees and breeding in large 

 numbers, and the same is true of the character of the fire. A 

 forest fire which not only kills but burns trees so badly that there 

 is a rapid drying of those standing is much less likely to be fol- 

 lowed by insect attack than one where there is only sufficient burn- 

 ing at the base to kill, specially if death is not rapid. Ap. 30, 

 May 15 and June 3 there were somewhat extensive fives in the 

 vicinity of Big Moose, and investigations by assistant 1). B. Young, 

 July 2, showed that inseci attacks had become nicely started in 

 the burning of May L5, more advanced in that of April :><h while 

 practically n'o signs of insect presence were observed in thai of 

 June 3. This would seem lo indicate thai I he trees are nol at- 



