Gentlemen ~
The grease patties with mineral salt and wintergreen are used for both
varroa and trachael mites.
According to the web site,  "The synergy of the active ingredient salt and
the inert wintergreen seem to have an effect on both Tracheal and Varroa
mites during times when brood is present, and has devastating results on the
mites during broodless times in winter."  Perhaps you could get in touch
with Dr. Amrine for further details.  The Url again is:
http://rnoel.virtualave.net/2000/index.htm for the complete recipe and
details.  Please note that it involves more than just patties placed on the
brood nest.
Wintergreen oil can be found by doing a search on Google.  I bought mine
from a person selling essential oils for soap making.  It can be bought at
most health food stores but you will most likely pay dearly for it.  The
mineral salt can be had from a feed dealer.
Sincerely,
Barb Miller
N. Central PA
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