Peter Borst wrote:
>
> Greetings
>         I hate to be the doubting Thomas but I personally don't see
> how the screened bottom board could work. I have watched mites cling
> tenaciously to bees and find it hard to imagine very many simple fall
> off and can't get back up. The mites that do fall off may simply be
> mites that are old and no longer strong enough to cling.

As I understand it, the main idea with the screened bottom board was
originally to increase the effectiveness of other mite control
measures. For example, fluvalinate, formic acid, or bee grooming
behavior are likely to "stun" or otherwise dislodge a lot more mites
than they actually kill.  If the stunned mites just fall to the bottom
board, recover, and climb onto the next passing bee, then obviously the
mite control is less effective than if they fall through a screen and
can't get back.

For that matter, it seems to me that the screen floors should be
good for delaying the development of resistance to fluvalinate and
other chemical treatments, because the "resistant" mites are probably
still affected by the chemical, they just aren't killed outright.
If being partially affected means that they still drop out of the
hive through the screen, then they won't be able to breed more resistant
mites.

So, is anyone carrying out serious, controlled studies to compare
the effectiveness with and without screened bottoms of, say, formic
acid or fluvalinate?

--
Tim Eisele
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