Varroa Management
When Varroa Treatment Fails: Resistance, Reinfestation, and What to Do
You treated on schedule, but the mite count barely moved. Here's how to distinguish true treatment resistance from reinfestation, application error, and timing problems — and what to do about each.
You treated the colony, waited the full duration, pulled the strips, and did your post-treatment wash. The mite load barely moved. Now what? Treatment failure is a defined, diagnosable event — not just bad luck. Working through the differential systematically tells you whether you made an application error, treated at the wrong time, lost mites to reinfestation, or are genuinely dealing with resistance. Each cause has a different fix. Defining Failure A post-treatment alcohol wash 3–4 weeks after treatment ends showing less than 50% reduction from the pre-treatment baseline is a treatment failure. Some context: 90%+ reduction: Successful treatment 70–89% reduction: Marginal — the treatment worked, but colony may need retreating soon 50–69% reduction: Poor efficacy — investigate why < 50% reduction: Treatment failure — mandatory investigation If you didn't do a pre-treatment wash, you have no baseline, and you can't determine efficacy. This is the most common reason beekeepers miss treatment failures. Always wash before you treat. Cause 1: Application Error This is the most common cause of apparent failure. Treatment chemistry is sound; the problem is how it was applied. Apivar (amitraz strips): Underdosing is the #1 error: Apivar requires 2 strips per 5 frames of bees. A
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Making Splits: How to Divide a Colony Before It Swarms
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Integrated Pest Management for Varroa: A Year-Round Strategy
IPM means using monitoring data to drive treatment decisions — not calendar dates. Here's how to build a Varroa management calendar that keeps mite loads below threshold year-round.
How to Monitor Varroa: Alcohol Wash, Sugar Roll, and Sticky Boards
Monitoring is the only way to know whether your Varroa load is at a safe level or approaching colony-threatening territory. Here's how to do an alcohol wash — the gold standard — and when each method is appropriate.
Varroa Treatments: A Beginner's Guide to Your Options
There is no single best Varroa treatment — each has tradeoffs in timing, temperature, and brood state. This is your overview of the main approved treatments and how to choose the right one.