OTHER THEN HORTICULTURAL OIL AND LIME SULFUR, WILL PYRETHRIN CONTROL RED BERRY MITES?
Sussex County Delaware
First, why do you think you have redberry mite? Second, from what I have read on this eriophyid mite, treatments at this time of year are too late and nothing will be effective. Finally, a pyrethrin probably will not provide much control over hort oil and lime sulfur, and at best only provide temporary management of the pest. Additionally, since it is a broad spectrum insecticide a number of natural enemies may be adversely affected. Reducing the number of natural enemies (generalist predator arthropods or parasitoid insects) on or around your plants has the potential to make the problem worse.
I do not work with fruit crops or fruit pests at all; therefore, my experiences are extremely limited. In ornamentals, a pyrethrin will not control eriophyid mites (a red berry mite is an eriophyid) well. I am sharing what appears to be an informative fact sheet from Michigan State regarding the pest. http://msue.anr.msu.edu/news/redberry_mite_damage_to_blackberries