> I checked a number of my hives Sunday and opened a few drone cells. These
> colonies have had normal mite populations and I was expecting to treat them
> within the next few months with Apistan. Instead of finding the normal mite
> load on the drone larvae ( around 50% with mites) I looked over some
> workers as well and still found no signs of mites!... Any thoughts?

We found varroa last year in bees brought into the honey house from our 3,000
hives and rushed to treat (once with Apistan (R)).  Six months later, extensive
sampling does not turn up even one mite.  Does that mean Apistan (R) killed them
all?  I don't think so.  Everything in nature has its rhythms and sometimes
factors combine to reduce populations.

An interesting note is that unless one is very careful, an uncritical observer
can ascribe the (temporary) natural decline of the pest to his own efforts,
rather than to good luck.  A good analogy is the caterpillar problem that we see
in the north of Canada.  Some years they strip the trees bare and make the roads
greasy with their crushed bodies, and the next we hardly see one.  FWIW, that is
why we hear honest, but unscientific people praising worhless 'cures' for many
things, including mites.

It'll be interesting to see what time and further testing shows up.

allen