-5- 



5. Zinc phosphide eroded from the bait material decomposes 

 quite rapidly in soils. Wetter the sodl the faster the 

 breakdown. 



6. Under moist, humid conditions carrier grains and other mater- 

 ials used to present zinc phosphide tend to mold and disinte- 

 grate becoming unacceptable to mice. 



With all of these conditions in mind plus the knowledge that 

 microtus are most active on warm, sunny days the following recommen- 

 dations are given: 



1. Pick a series of warm, sunny days to apply orchard mouse con- 

 trol materials. This is particularly true if material is 

 applied by a broadcast method. 



2. Consider placing at least part of the baits under some type 

 of protective cover .... i . e. , a square of roofing, a board, 

 or 1/2 a tire to protect bait. 



3. Keep a small amount of your orchard mouse bait in a dry con- 

 tainer. If a rain of any consequence does fall, run a 

 visual check on bait from several locations in the orchard. 

 Compare the two ; if the field applied material shows a loss 



of 15-20% of its zinc phosphide coating consider re-application 

 where necessary. 



THE MEDITERRANEAN FRUIT FLY IN MASSACHUSETTS: CAN IT HAPPEN? 



Ronald J. Prokopy 

 Department of Entomology 

 University of Massachusetts 



Whither the Mediterranean fruit fly? This insect, pictur- 

 esque to behold and s o enticing to an entomologist studying its 

 behavior and ecology, has for decades proven to be a devastating 

 pest of fruit wherever it has become established. Will it event- 

 ually reach Massachusetts, and if so, might it establish itself 

 here as a pest of our own locally growm fruits? Drawing upon 

 the extensive literature published on this insect (in particular 

 the fine article by Hagen, Allen, and Tassan in the March-April 

 1981 issue of California Agriculture), and upon my own research 

 experience with the behavior of Medflies in apricot groves in 

 Greece and coffee plantations in Hawaii and Guatemala, I will 

 attempt here to briefly describe the biology of the Medfly and to 



