22 DANGBB OF SPREAD OF GEPST AND BBOWN-TAH. MOTHS. 



Dataage to Plants. 



As just indicated, the damage to trees and shrubs may be very severe. The list of 

 food plants is very extensive. While there seemed at first to be a preference for pear 

 and apple, the larvae were found to feed also upon the stone fruits, as well as upon the 

 elm, maple, and several species of oak. Of late years there has been a very extensive 

 infestation of scrub oak and of the larger trees of the genus Quercus. In fact, the cater- 

 pillars feed generally upon all deciduous trees, on many shrubs, and even upon herb- 

 age. A list of over 80 different food plants was published by Pemald and Kirkland in 

 1903. Thousands of fruit trees in the vicinity of Boston have been killed by this in- 

 sect. Injury to woodlands and forests has not been a» severe as that accomplished by 

 the gipsy moth, and coniferous trees do not seem to be attacked, but the damage to oak, 

 maple, and elm in the wooded region has been sufficient to cause the forests to appear 

 brown in June in places, and complete defoliation for a series of three or four years has 

 brought about the death of many trees. Even where the tree survives, its growth has 

 been checked, and there is a timber loss. 



453 



