Trevor,
 
Two years ago at the Tennessee State Beekeepers Association Regional
Meeting in Memphis we heard about a company that had a machine that
would heat your hives to kill varroa( they would do this for a small
fee).  The state association was going to test this out, but I have
never heard anything else about it.  I assume it did not work.
 
Bill Hughes
Bent Holly Honey Farm
Brighton, Tennessee, USA
 
<<I had a visit from a German lady beekeeper last year who had
carried out some
work at University on using temperature for mite control before
becoming a
commercial beekeeper.
 
As I recall, they took sealed frames of brood out and heated them to
temperatures in the mid 40 degrees celcius.  The sealed brood could
stand it
but the varroa were killed by the temperature.
 
Apparently it was not considered suitable for commercial use as there
was only
a few degrees difference between the temperature needed to kill the
varroa and
the temperature at which the sealed brood was killed.
 
If some our beekeeping friends in Germany are on line, they may be
able to
provide more accurate details.
 
Trevor Weatherhead
AUSTRALIA>>