Conservation Methods Available to Growers 



Pcsticidal chemicals, nitrogen, and orchard 

 groundcovcrs are the three orchard components that can 

 be manipulated to promote biological mite control. 



Pesticide Management . Growers can create an 

 orchard environment more 

 favorable for predator mite 

 survival and reproduction by 1) 

 selecting pesticides that are as 

 safe as possible to predator 

 mites and 2) ending orchard 

 cover sprays as early in the 

 growing season as possible. 

 Relatively safe pesticides that 

 may be used without damaging 

 greatly predators do exist 

 (Table 2). In part, the relative 

 safety ofsome materials, such as 

 azinphos-methyl (Guthion^^), 

 is due to a natural evolution of 

 pesticide resistance in predators 

 such as A. fallacis, subject over 

 many years to the use of these 

 pesticides as orchard cover 

 sprays. The relative safety of oil 

 to predator mites is due to 

 selective timing, in that A. 

 fallacis is not on the tree at the 

 time that early season 

 applications are made to kill 

 European red mite eggs. All 

 classes of pesticides, including 

 herbicides, fungicides, and plant 

 growth regulators as well as 

 insecticides and miticides, 

 should be reviewed as to their 

 harmfulness to mite predators 



prior to use. For example, both lime sulfur and benomyl 

 are very harmful to A. fallacis, but for very different 

 reasons. Lime sulfur is directly toxic. Benomyl induces 

 sterility in female predator mites (Hislop & Prokopy, 

 1981) and thus, when used from June onward, destroys the 

 potential for the population to persist and grow. Miticides, 



