324 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 14 



LATE FEEDING LARVAE INJURIOUS TO APPLE IN PENNSYL- 

 VANIA INCLUDING SEVERAL NEW INJURIOUS SPECIES 



By S. W. Frost, State College, Pa. 



One of the most serious problems confronting the Fruit growers of 

 Pennsylvania is the control of various late feeding Lepidopterous lar- 

 vae which mar the fruit of Apple. As maturity advances each year 

 quantities of marketable fruit are seriously lessened by them. Many 

 of the species gnaw large cavities into the sides of the fruit, making them 

 worthless, a few burrow within the apples, while others produce small 

 scars or blemishes on the surface. The last mentioned type, although 

 often small in si-^e, detract largely from the quality of the fruit and 

 prevent them fr^m being packed and sold as first class apples. This 

 results in a lower percentage of marketable fancy fruit and consequent- 

 ly a tremendous less in returns to the or:hardist. A fiu"ther loss is in- 

 curred by the large proportion of fruit which drop in spring as a result 

 of the early attacks of leaf-rollers and other feeders. 



From our studies of the habits of Lepidopterous larvae injiurious to 

 apple, it appears that some workers have been misled concerning the 

 types of injuries and the species causing them. This may be because 

 the field has not been carefully investigated. Few workers have stud- 

 ied the types of injiu^ies of apples or correlated them with the work of 

 particular larvae. Some isolated species or groups of species have 

 been studied more or less in detail. Among these, Mr. Slingerland's 

 paper on "Green Fruit Worms", is the most notable. Among those 

 of more recent date is a paper by Fulton on "Insects injurious to Apple 

 Fruit", in which rome phases of the scarring of apple fruit have been 

 discussed. 



The work of the past deals chiefly with the early feeders of apple, 

 leaving the field of late feeders almost untouched. Leaf -rollers, for 

 example, have long been con^-idered as most injurious early in the sea- 

 son. In referring to injuries produced by this group, most writers lay 

 emphasis on the injury caused by the larvae webbing the leaves and 

 fruit together and the cavities produced in the sides of the fruit while 

 they feed from within these shelters. On the other hand little atten- 

 tion has been directed to the late feeding of Leaf-rollers or Bud-moths. 

 Fulton (1918) mentions them very briefly. In our investigations the 

 late feeders are an important factor and it has been found that over 



