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Allornate vs. Hvtry Middle Spraying For Apple Fesi ? in 1979 



William M. Coli and Ronald J. Prokopy" 

 Department o£ Entomology 



In previous issues of Fr uit Not es , we reported our 1977 

 and 1978 findings on the comparative effectiveness of alter- 

 nate-middle vs. every-middle spray treatments for apple pest 

 control. (See Fruit Notes 45(5) : 15-19 and 44(5): 15-35.) 



The 1979 results of alternate middle spraying fox apple 

 diseases have been reported in the November/December, 1979 

 issue of Fruit N otes . Here, we present (a) our findings on 

 alternate middle vs. every middle spraying for apple insects; 

 (b) further information on diseases, and (c) a cost-benefit 

 comparison with regard to insects, mites and disease control. 



Alternate middle spraying involves spraying alternate 

 halves of each tree on alternate spi;ay dates instead of both 

 halves on all spray dates. For example, in applying the first 

 cover spray, the sprayer would be driven up the middle between 

 tree rows A and 6 and return down the middle between rows C 

 and D, skipping the middle between rows B and C. For the sec- 

 ond cover spray, the sprayer would be driven up the middle be- 

 tween rows B and C, down the middle between rows D and E, and 

 so forth. If this pattern is followed on each spray date, it 

 would save 50% of spray material and application costs. 



Each of four test blocks in commercial orchards was divided 

 into 2 plots of 2-6 acres each. One plot received the alter- 

 nate middle program on each spray date throughout the season. 

 The other received tlie every middle urogram. Each grower used 

 an air-blast sprayer and a concentration (IX, 4X, etc.) of his 

 own choosing. Growers followed their normal spray schedule 

 and selected their own pesticide materials. Except in one 

 block, all trees were fully groivn, some on M7 rootstock, 

 others on seedling. Pruning was generally adequate to allow 

 for good spray penetration into tree centers. 



Monitoring of Pest Populations 



We utilized commercially available visual traps to moni- 

 tor populations of tarnished plant bugs, European apple saw- 

 flies, and apple maggot flies as well as pheromone traps for 



1 



Extension Pest Management Specialist (Entomology) and Extension 

 Tree Fruit Entomologist, University of Massachusetts at Amherst, 



Other field personnel were Glenn Morin, Senior Scout; Norman 

 Anderson, Clarence Boston, Annemarie Pennucci, and Mary Tubbs, 

 Scouts . 



