996 NEW YORK STATE MUSEUM 



large portions of the trunks and limbs of the unfortunate trees. Plate 



15 shows the condition of the trunk and lower limbs and plate 



16 is an enlargement of a portion of the preceding and gives a 

 better idea of the number of caterpillars. This outbreak occurred in a 

 large orchard of vigorous, fair-sized trees. It was not far from a small 

 piece of woods, but the hosts of caterpillars had evidently not invaded 

 the orchard from the forest. They came from eggs laid on the trees, and 

 their hatching had probably been delayed by the period of cold weather 

 above mentioned. This late, sudden outbreak occurred in a number of 

 orchards. 



An injury out of the ordinary was reported by E. L. Mitchell, Clarks- 

 ville, Albany co. His red and blackcap raspberries suffered severely from 

 these pests, the caterpillars crawling from the adjacent woods and strip- 

 ping the leaves from the plants in the nearest rows, working on them 

 much as the army worm does when it invades a grain field. The pests 

 were present in such large numbers as to threaten the defoliation of a 

 large part of eight acres of berry bushes. 



The abundance of these caterpillars afforded an excellent opportunity 

 for experimentation with contact insecticides. Good's caustic potash 

 whale oil soap no. 3 and his tobacco whale oil soap were tried, each 

 at the rate of 1 pound to 5 and 1 pound to 10 gallons of water. The 

 caterpillars were thoroughly sprayed as they were clustered on the trunks 

 and limbs, and about 15 minutes later samples of the victims were put in 

 cardboard boxes for subsequent observation. The stronger solution of 

 tobacco whale oil soap killed within a few days a considerably larger 

 portion of the caterpillars than the other. 



The record is as follows: 



Good's whale oil soap no. 3, 1 pound to 5 gallons 

 June 8. 99 caterpillars dead, 62 living 

 9. 6 caterpillars dead 

 15. 16 caterpillars dead 

 19. 10 caterpillars dead : 81.3% of the total killed 



1 pound to 10 gallons 



June 8. 87 caterpillars dead, 65 living 

 9. 5 caterpillars dead 

 15. 23 caterpillars dead 



19. 14 caterpillars dead : 84.8% of the total killed 

 Good's tobacco whale oil soap, 1 pound to 3 gallons 

 June 8. 135 caterpillars dead, 41 living 

 9. 5 caterpillars dead 

 15. 20 caterpillars dead 

 19. 4 caterpillars dead: 93.18% of the total killed 



