Field evaluaton of Apistan (R) and five candidate compounds for parasitic mite control in honey bees

Apistan(R) strips were highly effective in controlling adult Varroa jacobso ni (98% mite reduction) in honey bee colonies containing capped brood in au tumn (1996) in Nebraska. Plastic strips impregnated with bifenthrin reduced varroa populations by 46%, however greater control is needed to effectivel y manage varroa-infested bees. Colonies that received a formic acid packet, wintergreen grease patty or cardboard sheet coated with medicated chest ru b did not exhibit reduced varroa populations during the 45-day treatment. M ite populations in colonies receiving these treatments were not significant ly different from varroa populations in untreated colonies. In efficacy tests conducted in Kansas from autumn 1996 to the spring of 199 7, formic acid packets gave excellent control (87-99% mortality) of Acarapi s woodi, Menthol grease boards also reduced tracheal mite infestations (43- 70% mortality). However, colonies treated with medicated chest-rub sheets o r wintergreen grease patties contained as many mites as untreated colonies.