I have been reading an awful lot on Bee-L about the collapsing hive populations from last winter, and the Varroa. I did not, however, experience any decline due to Varroa, and have never had outrageous hive loss which I would completely attribute to Varroa. However, in the ever present purpose of protecting myself and my bees, I have been thinking about IPM. I already have a few Screened Bottom Boards in place, but I haven't noticed a huge effect (good or bad). What are some IPM strategies? I assume I have to have more in place than just Screened Bottom Boards. What are some other strategies that I can use? I don't like the concept of chemical treatment, and have used it somewhat as a last resort only.