134 THE EEPOKT OF THE No. 36 



live inside and gnaw cavities into the sides of the young fruit. Dr. Lintner 

 reports the same habit of the larvae and refers to some young pears that 

 were eaten into, sent to him by P. Barry, of Rochester, in 1888. Stedman 

 mentions the same kind of injury in Missouri and considers this the most serious 

 form of injury committed by the insect. To give some idea of the number of 

 larvae present the writer counted 17 worms in nine blossom clusters; Braucher 

 counted 21 larva? on one twig 21 inches long, and 19 larvre on another twig 22 

 inches long. 



The larva? also work on the leaves, rolling them and living within the roll. 

 Here, effectually hidden, they feed on the tender tissues of the leaves. When 

 disturbed they drop down out of their liiding places and remain suspended by 

 silken threads like cankenvorms. When all is quiet they climb back to their hiding 

 places and begin their work again. Their injuries to the leaves are often very 

 serious, especially when the larva? are abundant. Gillette says. '' I have seen 

 small orchards entirely defoliated by this species so that not a green leaf could l)e 

 seen." 



Life-History. 



Our observations accord with those of other workers for we find l)ut one 

 generation each year in Xew York. 



The eggs are deposited in greatest iiuml)ers during the last of June and the 

 first part of July. They are laid in small, oval, convex patches about as large 

 as the end of a lead pencil on the bark of the smaller twigs. Here they remain 

 until the following May or for a period of about ten months. 



The hatching period extends over an interval of two or three weeks although 

 the majority of the larva? appear about the time the buds are bursting. 



The full grown larva is about one inch in length, light green in color, -with a 

 black head, and black thoracic shield. It takes from three to four weeks for the 

 larva to become full grown. It pupates in a flimsy web in a rolled leaf and in 

 about twelve days tlie adult moths appear. These soon begin to deposit their eggs 

 thus completing the life cycle. 



Natural Exemies. 



The fruit-tree leaf-roller seems to have a number of natural enemies. We 

 bred at least four species of hymenopterous parasites from thr? larva? and pupa? in 

 our cages. Gill has recorded several species of ])ii'ds feeding on the larva? and has 

 also found a few insects which are predaceous on the leaf -roller; notwithstanding 

 this rather large list of enemies the leaf-roller ha-; not been held in check but in 

 spite of them has increased enormously at certain periods. 



Methods of Coxtrol. 



The leaf-roller has ])een one of the most difficult of lepidopterous apple pests 

 to control. Its habit of rolling leaves, tying them together, and living within these 

 protective coverings makes it difficult to get at. Attempts were made to control 

 the insect by thoroughly sjiraying the infested trees with arsenate of lead and lime- 

 sulphur about the time the buds were bursting, and again just before the blossoms 

 opened, but the results were not satisfactory. 



In the spring of 1911 a l)adly infested orcliard in western New York was 

 thoroughly sprayed, as the liuds were bursting wiih 2 pounds of arsenate of lead 



