Effects of Orchard Spray Program on 

 Plant-feeding and Predatory Spider 

 l\/lites in IVIassachusetts 

 Apple Orchards 



William M. Coli and Randolph CiurUno 



Department of Entomology, University of Massachusetts 



Since the inception in 1978 of the University 

 of Massachusetts Apple Integrated Pest Man- 

 agement Program, growers have heard a num- 

 ber of presentations concerning the importance 

 of selecting orchard pesticides based on their 

 impacts on not only the target pest but also 

 beneficial organisms. In recent years, the New 

 England Apple Pest Management Spray Guide 

 has contained a table of pesticide toxicities to 

 beneficial species, with data fix)m a number of 

 pubhshed studies conducted in Pennsylvania, 

 New York, New Jersey, Virginia, West Virginia, 



Massachusetts, and Canada. 



In 1987, we initiated a study of the effects of 

 orchard groundcover comix)sition on plant-feed- 

 ing and predatory mites. As a component of this 

 study, we reviewed the spray records of 28 

 commercial apple orchards in Massachusetts. 

 Spray programs that included carbamate insec- 

 ticides, pyrethroid insecticides, certain 

 acaricides, or certain herbicides known to be 

 detrimental to predatory mites were classified 

 as "hard" programs. Those that avoided such 

 materials were classified as "soft" programs. 



Fruh Notes, Fall, 1993 



