> "Fumidil-B is best prepared at a concentration in the range
> of 75 to 100 mg.fumigillin activity per gallon of 2:1 sugar
> syrup."
 
I believe this refers to pure fumigillin.
 
> The instructions now leave the confines of reality
> as they further recommend," When only (1) or (2) colonies
> are to be treated, the syrup may be made by dissolving a
> rounded teaspoonful (3.75 to 5 grams ) FUMIDIL-B per galon
> of syrup."
 
I believe this refers to fumigillin with filler (that is, as it is
found in the FUMIDIL-B bottle).
 
> At the 5 gram/gal. rate, you are overdosing your bees
> by a factor of 10 to 1.
 
If the filler to fumigillin ratio is 10 to 1 (or more likely 9 to 1),
the dosage would be closer to correct.
 
Conrad Sigona
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