THE PEACH SAWFLY. 2S7 



showed some damage it was not noticed in another neighboring 

 orchard, thus indicating that the insect was quite local in its 

 work. This year it was more widely distributed, being found 

 in all of Barnes Brothers' orchards, and appeared less local in 

 its movements, though this feature could not be definitely 

 observed, as the badly infested locality of the previous season 

 was all thoroughly sprayed this year. In the orchards of 

 Messrs. Hopson, Hall and Lyman the work of the insect was 

 observed over considerable areas, but was nowhere serious. 



The work of the insect is very characteristic, and is first 

 noticed by the rolling of the leaves and later by their shredded 

 appearance as shown on Plate I. This is more fully described 

 under habits of the insect. 



Food Plants. 



This sawfly seems to be confined almost entirely to the peach. 

 The foliage of the native trees and plants in the vicinity of the 

 peach orchards, especially those belonging to the rose family, 

 was carefully examined. The only plant found on which eggs 

 had been laid and larvae were feeding was a small bush of the 

 wild black cherry, Prunus serotina Ehrh. This was in an old 

 division wall between two portions of the orchards in the badly 

 infested locality. Other black cherries in the vicinity of the 

 orchards were examined but no eggs or larvae were found on 

 them. Many adults were seen resting on the leaves of apple 

 trees, a number of which were in the peach orchard, but no eggs 

 were found on them. On Japanese plums and sour cherries near 

 the infested orchards no trace of the insect was found. In 

 one of the breeding cages, where there was no chance to 

 oviposit on peach foliage, a few .eggs were laid on common 

 sorrel, Rumex acetosella Linn. 



These observations are contrary to the usual habits of native 

 insects that become serious pests. Ordinarily the species will 

 be found feeding on a number of closely allied wild plants, and 

 gradually begins to work on cultivated species, the injury increas- 

 ing from year to year. A new pest suddenly breaking out in 

 numbers and confining its work to a single cultivated plant, as 

 the peach sawfly is apparently doing, strongly suggests its being 

 an introduced species. In regard to the peach sawfly it is cer- 

 tainly hard to answer the question, — where did they all come 

 from? 



