U. S. D. A., P.. E. Bill. fiS. Tart V. D. F. I. I., January 8, 1908. 



PAPERS ON DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 



THE LESSER APPLE WORM. 



(Enamioiiia prunivora Walsh.) 



By A. L. QXTAINTANCE, 



In chan/e of Deciduous Fruit Insect Investigations. 

 INTRODUCTION. 



During the past three years the species known as Enarmonia pru- 

 nivora has been found ver}^ commonly infesting the fruit of the apple 

 in various parts of the United States, in some sections so abundantly 

 as to cause serious loss to orchardists, the insect ranking in impor- 

 tance as an apple pest close to the codling- moth. 



The small, fusiform, flesh-colored larva% about three-eighths of an 

 inch long, injure the fruit around the calyx by eating out shallow 

 cavities or boring holes into the flesh from one-fourth to one-half inch 

 or more in depth, in the ripening fruit occasionall}' penetrating to the 

 seeds. The surface of the fruit, especially in the calyx basin, is also 

 injured, the larva; working beneath the skin and eating out galleries 

 or large blotch mines, frequently with holes or borings extending 

 more deeply into the flesh. The work of this species resembles rather 

 closel}' that of the codling moth, and the similarity of the larva 

 to the codling moth larva and a further similarity in the life his- 

 tories and habits of the two species have doubtless been responsible 

 for the almost complete oversight in the United States of this species 

 as an important enemy of the apple. 



HISTORY. 



The lesser apple worm was discovered by Walsh in Illinois during 

 July, 1867, in the course of a study of the plum curculio {Conotimche- 

 lus nenuphar Hbst.). "Walsh found the larva in plum and about a 

 month later bred out numerous moths from the same fruit. In the 

 Prairie Farmer for December, 1867, page 359, under the caption 

 " The plum moth,"' he makes brief reference to his discovery, and the 

 same 3'ear, in the First Report of the State Entomologist of Illinois, 



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