The "Claims" for the are based on successful use over the past seasons and
discussions with many other keepers in the area that have been using
Formiic acid for many seasons more than I.  Hardly scientific I agree,
however, the results, costs and benefits are speaking for themselves.  As I
mentioned, I also would like to see the Scientific study bear out what is
being claimed.

Please note that I didn't use the words "impossible" nor say "cannot become
resistant" and I don't think any responsible commentator would say such
thing.  That is why we are looking for papers that can add to the body of
evidence in support of Formic.

I believe the reason for the effectiveness of Formic acid is that it is
more like a sledge rather than a finishing hammer to kill the mites.
Formic acid attacks dissolves the mites chitinous shell and the only way to
develop a resistance to that is for the shell to get thicker or evolve a
different shell.  A thicker cell would result in a much bigger mite,
removing the advantage of their small size.  The reason the bees can
tolerate the dissolving fumes of the acid is simply their shells are
thicker.  You can tell the bess don't like the acid either, as on hot days,
they gather in much larger numbers than ususal at the entrance.  Just
emerged bees can be killed by the Formic treatments as their shells have
yet to harden fully.

The slowness of mites to develop a resistance seems to have alot to do with
how Formic kills them.  Developing a resistant "skin" is a much more
dramatic evolutionary adjustment than then how the chemical strips kill.  I
believe the strips attack from the cellular level, which is much easier for
mites to evolve a resistance to than Formic acid.  Hence the
aforementioned, Sledge vs. Finishing hammer analogy!  Perhaps, over the
years the mites may develop a resistance, however, opposed to the strips
resistance that seems to develop after about a year or so of use Formic
acid still looks better and does by you time for other alternative
treatments to develop.

In my initial message, I failed to mention that the effectiveness of Formic
acid is largely related to weather conditions.  If you experience cool
weather during the treatment period then the effectiveness of Formic acid
is reduced sharply.  Formic treatment requires warm/hot weather to vaporize
the acid to circulate through the hive and kill the mites.  When the
weather is too cool, the amount of Formic circulating may not reach lethal
levels, thus reducing the mite kill.

Bottom line for me, having used both methods (strips vs. acid), acid is
superior.

Cheers,
Mark Walker.


><concerning formic acid:>
>> Tracheal mites with no fear of a resistance developing, unlike Apistan
and
>> Checkmite.
>
>I am very puzzled by this.  What are the grounds for the claims that the
>mites will never become resistant to formic acid or oxalic acid?  I saw
>this claim in several posts about oxalic acid earlier today, and now
>here about formic acid.  So far, I don't remember seeing anyone challenge
>this.
>
>I personally don't see the justification for the claim.  If the chemical
>doesn't kill the bees, then why on earth would it be "impossible" for
>the mites to at least develop the same level of resistance as what the
>bees already have?  Remember that "resistance" doesn't mean "absolute
>immunity to the effects of the treatment", it just means that the
>resistant mites can tolerate a little bit more, so that dosages that
>will kill the mites also become dangerous to the bees.
>
>So, when claims are made that mites cannot become resistant to a
>particular treatment, is there any grounds for this, or is it just
>wishful thinking?
>
>--
>Tim Eisele
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