Tartaric acid has been recommended for use in syrup persistently for many
years. However, studies by Bailey in England as far back as 1966
showed that such use can reduce the life of honeybees if natural nectar is not
coming in when the treated syrup is fed.
 
This information was included in The Abc & XYZ of Bee Culture, 36th
edition, in 1975, page 281. Unfortunately, the same edition included
information on another page (454) telling how to mix tartaric acid to
make invert sugar, without any cautions of possible problems.
 
No doubt more specific information is available in the literature from
the 1966 period, but I have never looked for it. Perhaps someone else has
information.
 
Dick Bonney
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