FIFTY-FIRST ANNUAL, REPORT. 63 



The one thing which must be kept in mind, regardless of the method 

 used, is that all spraying for pear psylla must be very thoroughly done. 

 No ordinarily good job of spraying will get results as every adult, egg 

 or nymph nuist bo well covered to be killed. I have watched this closely 

 this spring and the men who really sprayed got results. Growers who 

 did not get results have told me that they were sure the fault was the 

 application and not the method. 



No definite rule can be laid down as to how the spraying shall be 

 done, but on trees of much height I think there should be one man on 

 top of the sprayer and one on the ground. 



GRAPE DUSTING. 



The grape dusting work has again failed to give any definite results 

 concerning rot control as there was so little rot developed on the checks 

 that no d(>finite conclusions could be drawn from the work. Particular 

 attention was given to leaf hopper control and applications were made 

 as i-ecommended by Professor Pettit but satisfactory results were not 

 secured from every application because of a batch of poor material. 

 However, with a satisfactory nicotine sulphate dust which is now avail- 

 able, I am confident that better results will be gotten. This dust is 

 made up of nicotine sulphate and hydrated lime, the lime, of course 

 being used as the carrier. The material was tested in a small way late 

 in the season and was very effective against the leaf hopper nymphs. 

 Its successful use will probably depend upon a satisfactory duster and 

 I hope to have for next season a duster which will give much better 

 distribution of the material than anything that has been available in 

 the past. 



RASPBERRY SPRAYING. 



The schedule now recommended for anthracnose control on rasp- 

 berries calls for three applications: one when the plants are dormant, 

 second when new shoots are six to eight inches high, and again just 

 before blossoming. This number of applications gives satisfactory con- 

 trol but of course it would be very desirable to reduce the number of 

 applications if it can be safely done. I have felt that if a planting has 

 once been cleaned up, it may be possible to get good commercial control 

 with less than three applications so carried through an experiment this 

 season to determine the point in question. 



The field was divided into four plots. One was left unsprayed as a 

 check, one was sprayed once when dormant, another sprayed when 

 dormant and when growth was about 8 inches high, and the fourth was 

 sprayed the regular schedule of three applications. This work was 

 done near South Haven by Mr. Johnston. It is not safe to make recom- 

 mendations from one season's work but the results are very promising 

 and indicate that the number of applications may be reduced. The 

 unsprayed plot was badly diseased. The one sprayed three times was 

 practically free from anthracnose. The plot sprayed at the first and 

 second application showed some anthracnose but nothing at all serious 

 and the part which received the dormant only was decidedly better 

 than where no spraying was done. I do not care to make any recom- 

 mendations regarding this now but simply givo those losults as n report 

 of progress. 



