> Considering the fact that varroa quickly becomes resistant to
> amitraz, and considering it has been used for 30 years, I would steer
> clear of it.

I hear this often and recall learning in an informal meeting that the
initial dose required had been multiplied by ten at that time in 2005.

Interesting.  Those same guys apparently still use it -- if they can get it.

The very fact that it has been in use for 30 years and still seems to be 
the best chemical says something to me.

So, what exactly does 'resistance' mean?  Are we being deceived by
oversimplification and black and white thinking?  Seems to me that we 
are getting a of of smoke and not much hard info.

Apparently, resistance does not necessarily mean total immunity to the
chemical, but rather describes a continuum from no ability to survive in
the presence of the chemical to total immunity to its effects.

Moreover this resistance may vary over the pest population, may or
may not be persistent and may fade quickly -- or slowly.

Additionally, as the pest becomes more tolerant to the chemical, is it
possible the host, our bees, are also increasing in tolerance?

As I mentioned again here recently in reference to fluvalinate, that it 
was reported ten years ago that fluvalinate apparently still knocks down 
resistant varroa even if it does not kill them.

I received absolutely no response, but ask again, does a chemical have 
to kill to be useful?

In our cold climate, simply knocking down mites in large numbers has 
great potential as we can put a sticky board or screen below, or time 
the treatment to when the lower hive is too cold for weakened mites to 
survive.

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