288 Bulletin 311 



It is just possible that the arsenate of lead in water alone, instead of 

 in combination with lime-sulfur, would have been more effective. It is 

 probable, however, that a stronger application of poison will be necessary 

 in order to control this insect. Either more arsenate of lead will have to 

 be applied, or a substance containing a greater percentage of arsenious 

 oxid must be used. Something must be found that, when applied to the 

 bursting buds, will be powerful enough to kill the young caterpillars 

 even though they get very small quantities of the poison. 



To sum up, then: (i) We would advise a thorough drenching of the 

 trees with lirne-sulfur at scale strengths for a dormant spraying to prevent 

 the eggs from hatching, provided one is going to spray for the San Jose 

 scale or the blister mite; we are not yet ready to recommend a spraying 

 for the eggs of the leaf -roller alone. This application should be made as 

 late as possible in the spring before the buds burst. (2) We would advise 

 a thorough spraying with arsenate of lead at the rate of 25 to 3 pounds 

 to 50 gallons of water, before the buds burst but while they are swelling 

 or just as the tips begin to show green, and again before the flower buds 

 open. These applications will also catch the bud-moth larvse, which are 

 serious pests. 



