Well, I mainly go by experience and what works. I have seen some
gawdawful homemade bottom boards in my time and have never had
problems with the modern treated bottom boards. I have some bottoms
that are 40 years old and made of evreything from masonite to plastic
signs. I do bee removals and have seen bees living in fuel tanks, paint cans,
and machinery; so I pretty much discount all the hand-wringing.