Reviewed notes and corrections
The sheet’s four-hour claim must not be attributed to Kablau’s 41°C two-hour experiment. That study does not validate a four-hour protocol for an occupied hive. Longer exposure can change both efficacy and harm; a temperature that was studied for one duration is not automatically safe for another. Treat this sheet as a discussion of a proposed heat approach, not a validated operating instruction.
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The original image is displayed above. Where its wording differs from these reviewed notes, use the corrections on this page. The downloadable image itself has not yet been revised.
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VarroaDestructor.com · Reviewed October 14, 2026
