> > >Oxalic acid is hurting (weakening) bees and open a gate for secondary
> > > diseases ( for instance - virus).
>
> Apidologie 35 (2004) 453-460

I've checked the math in this paper, and the dose is reasonable, .005mg OA
per larva,vs .016mg OA theoretical if 3 ml of 3.5% solution per seam is
dribbled.
Members may also wish to check Apidologie 34:181-188 and 32:127-138 for OA
toxicity

Oxalic acid is absorbed through bee's cuticle, as well as being ingested.
It is not gentle on the bees.  I would not overuse it!
As far as its use, I wouldn't recommend more than one weak dribble during
the broodless period per year, although I have test colonies that are
thriving after 3 strong treatments 5 days apart in late summer.
It's a trade off, as with all chemicals, of keeping your bees alive, hurting
the bees or brood, operator safety, and whether you're contaminating the
combs or honey.
On most of these points, OA is positive.  As far as I'm concerned, ANY
chemicals are stopgap measures as we move toward better bee genetics and
biotechnical methods.  My series of articles in ABJ are moving in that
direction, and I will return to this subject of OA problems.
Randy Oliver

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