Published March 31, 2026 · Last Updated August 26, 2026
Three methods dominate varroa monitoring: the alcohol wash, the sugar roll, and the sticky board. They trade off accuracy, cost to the colony, and effort. Here’s how each actually works and which to reach for.
Alcohol Wash: The Accuracy Standard
The alcohol wash kills the sampled bees, but it’s the most accurate field method available, and it’s what treatment-threshold research is calibrated against.
What you need
| Item | Recommended option | Why |
|---|---|---|
| Solvent | 91% isopropyl rubbing alcohol | Best mite recovery; dissolves wax flakes that can obscure counts |
| Sample container | ~125 mL cup, filled level | A level half-cup holds roughly 300 bees — the standard sample size |
| Shaker | Double-jar shaker with mesh insert | Separates mites from bees quickly in the field |
Step by step
- Pull a frame with open brood and nurse bees. Check both faces for the queen before shaking — never sample a frame with the queen still on it.
- Shake bees from the frame into a wide container. Older foragers tend to fly off, leaving the nurse bees that best represent the colony’s actual mite load.
- Measure a level half-cup (~300 bees) into your sampling jar with the alcohol.
- Swirl for at least 60 seconds. A mechanical agitator (Randy Oliver’s “Smokin’-Hot Mite Washin'” method uses ~300 swirls in 60 seconds) gives around 95% mite recovery; vigorous hand-swirling for 60 seconds is a reasonable substitute.
- Pour the liquid through the mesh insert or a fine strainer, separating mites from bees. Hold the container to the light and count.
- Divide the mite count by 3 to get an approximate percent infestation for a 300-bee sample (e.g., 6 mites = ~2%).
Sugar Roll: The Non-Lethal Option
The sugar roll (or “sugar shake”) uses powdered sugar instead of alcohol, coating the bees so mites lose their grip and fall through a mesh lid — then the bees are shaken free and returned to the hive alive. It’s the right choice when you want to sample the same colony repeatedly without killing bees each time, such as in a small apiary where losing 300 bees per check adds up.
The tradeoff is accuracy: a properly performed sugar roll recovers roughly 85% of the mites an alcohol wash would find on the same sample. Common mistakes that push that accuracy lower: using damp or clumped sugar, not shaking long enough for the sugar to fully dislodge mites, or sampling from a frame with mostly capped brood (fewer phoretic mites available to dislodge). Powdered sugar rolled onto the sample and left to sit for about a minute before shaking gives sugar time to work its way between the mite and the bee’s exoskeleton.
Sticky Boards: Passive, Continuous Monitoring
A sticky board sits under a screened bottom board and catches mites that fall naturally from the colony over a set period — typically 24 to 72 hours. It doesn’t require handling bees at all, which makes it useful for tracking trends between active samples, but it’s less precise for a single-point decision: natural mite drop varies with treatment activity, brood cycles, and even robbing behavior nearby. Count the total mites caught, divide by the number of days the board was in place, and compare the daily average against your threshold rather than treating a single day’s count as definitive.
Which Method Should You Use?
- Making a treatment decision right now: alcohol wash. It’s the most accurate and the fastest to a clear answer.
- Repeated sampling on a small number of hives, or a queen you want to preserve: sugar roll.
- Tracking a trend over days without disturbing the colony, especially post-treatment: sticky board, alongside an occasional wash or roll to calibrate.
Whichever method you use, the value comes from consistency — same sample size, same frame type, same time of day where possible — so counts are actually comparable from one check to the next. For guidance on how often to test and how to read the numbers you get, see varroa mite testing: timing, frequency, and interpreting your counts.
FAQ
Is the sugar roll as accurate as the alcohol wash?
No — a well-performed sugar roll typically recovers about 85% of the mites an alcohol wash would find on the same sample. It’s still useful, especially when you don’t want to kill the sampled bees.
How many bees should I sample?
A level half-cup, which is roughly 300 bees, is the standard sample size for both alcohol wash and sugar roll testing.
Can I reuse a sticky board reading from just one day?
You can, but a single day’s natural mite drop is noisy. Averaging over 2-3 days gives a more reliable trend than one reading alone.
