-2- 



Two types of sprays are available, those containing ammonium sul- 

 fajnate and those containing sodium chlorate. The Eimmonium sulfamate type 

 is slightly more effective in killing chokeoherries, is easier to handle, 

 leaves no undesirable residue in the soil, and no fire hazard is involved 

 in its use. On the other hand, it is more expensive per pound, and is cor- 

 rosive on metal parts, particularly copper. 



The manufacturer has made several suggestions for overcoming the 

 corrosive effect of ammonium sulfamate. Mix oil with the spray or coat the 

 inside of the tank with grease. Hanging a strip of zinc or putting some 

 granulated zinc in the spray tank is said to help. Most important is to 

 wash out the sprayer thoroughly after use. Adding hydrated line or baking 

 soda to the last rinse water is recommended. Probably adding a couple of 

 pounds of spray lime to 25 gallons of water and washing the sprayer out 

 thoroughly are most practical for the fruit grower with a large sprayer. 



— J. S. Bailey 



NOTES ON FRUIT IHSECTS 



Apple Maggot { The number of maggot flies which had emerged in 

 cages at V^altham on June 23 vms 72, equal to 24^ of the expected number. 

 This nuiiiber of flies has not been collected in other years until July 5 

 to 10. In addition, at least 1 maggot fly has emerged from last year's 

 cage, having been in the soil since Septembei*, 1942. These observations 

 indicate that either emergence is 2 to 3 weeks earlier than usual or that 

 the number of flies surviving the v/inter is greater than normal, or both. 

 Also, that some flies which did not emerge last year, probably because of 

 the dry soil in July, will appear this year. 



For maggot fly control, spray or dust is usually applied when the 

 emergence reaches 15 to 20j2, and again just after the peak of emergence. 

 Therefore, the spray program may be adjusted as follows: Where the 2nd 

 Cover spray was not applied before June 18, this application will serve 

 as the first spray against maggot. The 3rd Cover spray should be timely 

 July 5 to 10. On early maturing varieties this should be sufficient pro- 

 tection for the season. On late maturing varieties, a 4th Cover spray 

 July 25-August 1, may be necessary to protect against late migrating maggot 

 flies, and also to control 2nd brood codling moth and l^iaf roller. If dust 

 is applied, 75-25 or 70-30 sulfur-lead arsenate dust should be used in the 

 4th Cover , 



If the 2nd Cover spray was applied before June 18th and the rainy 

 period, June 19-22, the 3rd Cover spray will be timely June 30-July 3, and 

 the 4th Cover spray about July 12-15. This will make another application 

 for late codling moth and leaf roller advisable July 25-August 1. 



Green Apple Aphis t The green apple aphis lives on the apple 

 throughout the summer usually concentrating on watersprouts after July 1. 

 Its abundance is governed largely by the number of predators, such as lady- 

 bird beetles, lace vang flies and syrphus flies. These beneficial insects 

 were abnormally abundant this spring but appear to have been greatly reduced 



