This summer I pollinated our melon fields and another beekeeper pollinated an adjacent field of melons, our pallets of hives were 25 feet apart. Since we get along pretty well he told me that since bees coming back near dusk will sometimes go to the nearest hive and hole up I should seriously consider treating for mites since his hives were infested. Three weeks ago I did an oxalic acid treatment and each treated hive has dropped thousands of mites. Doesn't matter how you get mites, you're going to get them. What are you going to do to control them?