In a message dated 14/02/00 5:24:45 AM Mountain Standard Time,
[log in to unmask] writes:

<< I agree that a bottomboard under the screen would allow the fallen mites
the
 chance to come back through the screen and re-attach to thier host, unless
 they are somehow trapped with a sticky board or other means.  Does your
 screen attach to a frame which acts as the bottom board or does the screen
 attach directly to the bottom of the hive body with a spacer allowing
 entrance on one side? >>

It should be noted that research by Dr. Jeff Pettis at the USDA has
demonstrated that if Varroa mites are seperated by a small distance from the
bees (I can't remember how much- maybe 1.5 inches- does anyone on the list
know?), they remain motionless and do not find their way back onto the bees.
You do not need the mites to fall a foot- they only need to fall a few inches
and bee excluded from bee traffic.  No stickyboards are required- that is the
point.  I cannot comment if the inserts made by these manufacturers meet the
minimum distance determined by Dr. Pettis- you may want to ask the
manufacturers if they took his work into account when designing the inserts-
Dr. Pettis's work on screened inserts appear in an ABJ issue last year.

Regards
Adony