I wonder if the waxy coating on the bees is deteriorated by acids
(formic/oxalic) thus providing a way in for pathogens and/or a way out for
moisture, compromising the bees.

A way to kill a poison ivy vine is to spray some of the leaves with
horticultural vinegar (about 15% acetic acid solution..stronger than
"eating" vinegar).  The acetic acid in the vinegar strips the leaves of
their waxy coating and the vine dehydrates through the leaves and dies.

Just a thought...

Ramona

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