Insecticide Combinations

[Ashby Chadburn]

I have been growing orchids for several years, but recently I have suffered an attack of false and regular spider mites during the Summer two years in a row. I have used Avid to treat the false spider mites and Bayer 3 in 1 to treat the regular spider mites. I would like to combine the two insecticides because it is very labor intensive to spray all the orchid leaves top and bottom with both products. I read in the AOS guide to pests and diseases that there are charts that tell you which insecticides can be safely combined and in what proportion. So far I have had no luck finding such charts. Anyone have experience or a source for this information? Thanks for your help.