Have you read the  article by Steve Sheppard in the Jan '04 Bee Culture?
Looks like in the not too far future we may possibly have another tool in
the toolbox; but unlike oxalic acid it looks like Dadant will most likely -
if I am reading between the lines correctly - package the new tool:

On Fri, 3 Oct 2003 14:46:09 -0600, Rosalind James <[log in to unmask]>
wrote:

"I am a Research Entomologist (Insect Pathologist) at the USDA
Agricultural Research Service's Bee Biology and Systematics Lab in
Logan, UT..... I am currently working on developing a microbial control for
varroa mites, that means, yes, the use of fungi for controlling varroa".
"... but we are now at the point of doing field tests in collaboration
with Dadant to determine effective doses and methods for application.  The
biggest problems..."

Since Steve Sheppard reports that this stuff, Metarhizium anisopliae, in
field studies "was equal to that achieved with the conventional treatment
Apistan(R)" this just might work.  Interesting to note that this was a
thread that started back in May of last year on the Bee-L:
http://listserv.albany.edu:8080/cgi-bin/wa?A2=ind0305E&L=bee-l&P=R295. It
appears that a great amount of work has been accomplished. Let's hope that
if it does come to fruition that the FDA approved pesticide and its
application can be purchased at a reasonable price since it was developed
with taxpayers dollars.

Chuck Norton
Norton's Nut & Honey Farm
Reidsville, NC

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