> I have been using this type of floor for nearly twenty years and
> I would be unlikely ever to use a solid one in future.

I am looking seriously at using screened bottom boards starting next year.
I have read here in the past that 6 mesh is the perfect size, but that it is
hard to find.  I understand that 1/4" and 1/8" mesh are easier to find, but
1/4" will not keep out the wasps.

Two questions:

1) Will varroa reliably fall through a 1/8" mesh?
2) Does use open mesh floors promote raiding of hives by small ants?

Frank.
-----
The very act of seeking sets something in motion to meet us;
something in the universe, or in the unconscious responds as if
to an invitation.  - Jean Shinoda Bolen