The Fruit-tree Leaf-roller 287 



are so small and so like in color to the bark that they cannot be found 

 with any degree of facility. It would take too much time and labor to 

 prove at all economical. 



On the other hand, in a severely infested orchard it might be entirely 

 practicable and economical to prune the trees rather severely, especially 

 those known to bear egg masses. Judicious pruning is a good orchard 

 practice, anyhow. We found only the smaller branches, twigs, and fruit 

 spiirs bearing the eggs. When taken off, these should be promptly burned. 



Gillette, of Colorado, has recommended the use of kerosene emulsion 

 to destroy the eggs, and also a thorough coating of whitewash " upon the 

 trunks and main limbs " to destroy the young larvae as they are eating 

 their way out of the eggshells. In his later experiments, however, he 

 comes to the conclusion that whitewash and lime-sulfur and salt do not 

 give much promise. During the coming season we hope to try the lime- 

 sulfur wash applied as late as possible before the eggs hatch in the spring. 

 It will be necessary to use liberal quantities of the wash and to drench 

 the tree, so as to be certain of coating the egg masses on the smaller branches. 



Gillette found that 33 per cent kerosene emulsion applied to the egg 

 patches killed all the eggs. He says, " The application may be made 

 any time after the leaves drop in the fall and before the buds begin to swell 

 in the spring." During the season of 1895 he was able to control these 

 leaf -rollers satisfactorily in the college orchard through an application to 

 the trunks and the larger limbs, early in the season, of a strong kerosene 

 emulsion, and by the use of paris green on the foliage later. 



The miscible oils, if they do not injure the trees, would be much more 

 convenient to apply than is the kerosene emulsion, and would probably 

 be about as effective. We hope to determine these points during another 

 season. 



One would think that a good spraying of the infested trees with arsenate 

 of lead added to lime-sulfur just before the buds break, and another before 

 the blossoms open, would control the pest, but in this we were disappointed. 

 The worst-infested orchard was sprayed once by the owner for the blister 

 mite and bud moth, about as the buds were swelling. At this spraying 2 

 pounds of arsenate of lead were added to 50 gallons of the mixture. On 

 May 9 Mr. Braucher, who was in the field at work on the codling moth, 

 found that the leaf -rollers were hatching in abundance, and on May 13 

 he sprayed thirteen Baldwin trees, putting on 200 gallons of lime-sulfur 

 mixture to which 8 pounds of arsenate of lead had been added. This was 

 just before the blossoms opened. Later, after the petals had fallen, the 

 regular codling-moth spraying was given, making three poison sprays 

 applied to these infested trees. We were much disappointed to find that 

 the larvae were not visibly lessened in numbers by these applications. 



