74 



cherries are also subject to attack: in fact, no varieties are positively 

 immune. It is probable that the species lives normally on some sour 

 species of native cherry, and if such should prove to be the case these 

 trees should be destroyed or the fruit carefully picked if it have am T 

 commercial value. 



METHODS OF CONTROL. 



The brief account furnished of the life history of this species is 

 indicative of the difficulty of destroying it or preventing its ravages. 

 We can not destroy it with insecticides or capture it by jarring, as in 

 the case of the plum curculio, nor by gathering the " ; windfalls, "as 

 for the related apple maggot. The egg being inserted under the skin 

 and the larva feeding still deeper in the fruit, can not be reached, nor 

 can the fly. which does not feed to any appreciable extent, if at all. on 

 the fruit. This leaves the pupa stage as the only vulnerable one for 

 attack, and the skin of the puparium is so compact that it is probably 

 impervious to any ordinary liquid which would not injuriously affect 

 the tree or the soil. 



The most feasible remedy that sugg-ests itself is careful cultivation 

 of the orchard, but this has been practiced by some of the most suc- 

 cessful orchardists of New York, and injury was evidently not lessened 

 thereby. An explanation urged by Mr. Slingerland is that the puparia 

 are too small to be crushed, and it is therefore suggested that remedies 

 advised for certain species which have similar habits and infest currants, 

 be employed, remedies which have been advised for years in this 

 Department. These consist in late fall c r early spring plowing, so 

 deeply that the puparia will be buried far enough beneath the surface 

 as to render it impossible for the flies to emerge. Where a few valu- 

 able trees only are affected the surface soil could be removed to a 

 depth of about an inch or a little more, and either thrown loosely into 

 a hen yard or upon a much traveled highway, or buried deeply, all of 

 which methods would insure the death of the puparia. 



Hens have been observed to destroy the puparia, and if the soil 

 under the infested trees were lightly raked and temporary wire 

 nettings were placed around the trees, hens could be confined in this 

 inclosure and would soon destroy the pest. 



Clean culture must, of course, be observed, which would include the 

 picking of all of the cherries from the trees, and the destruction of 

 such few windfalls as might be found. 



In conclusion, it should be stated that various other remedies than 

 those mentioned have been tried without success in other countries 

 against insects of similar habits. These include attracting to lights, 

 the use of deterrent substances to prevent the flies from ovipositing, 

 spraying with a great variety of insecticides and other substances. 

 Of these one is deserving of mention, a mixture of sulphur and 

 caustic soda in solution, which gave partial success. 



