From an alcohol wash or sugar shake: mites per 100 bees, set beside the thresholds published guides print for that time of year.
How to read it
- Mites per 100 bees is the mites counted divided by the bees in the sample, times 100. With exactly 300 bees it is the mite count divided by 3.
- The guides do not agree on one number, and they word their figures differently ("1 or more", "more than 1"). The table shows each figure as printed, and the result keeps each source's wording: for "1 or more" it says whether your reading meets it, for "more than 1" whether it is more than 1.
- The Honey Bee Health Coalition calls the alcohol or soap wash the more reliable method; Ontario's and Perennia's figures are for alcohol wash.
- Thresholds vary by region and colony. On Prince Edward Island, the provincial apiarist can say which figures to use.
- This page does not recommend a treatment. Follow the guide you use and the label of any product.
Thresholds as printed
| Source | Spring | Summer | Fall | Going dormant | Method, wording |
|---|---|---|---|---|---|
| Honey Bee Health Coalition, Tools for Varroa Management, 9th ed. (2026) | 1 | 2 | 2 | 1 | alcohol or soap wash, or sugar shake; "1 or more" in spring, "2 or more" at peak and decreasing population, "1 or more" when the colony is dormant |
| Ontario.ca, Treatment options for honey bee pests and diseases (updated 30 Oct 2026) | 1 | 2 | — | — | alcohol wash; "more than 1" in spring, "more than 2" in August; no fall figure on that page |
| Perennia / ATTTA, Summer Disease and Pest Monitoring (2016) | 2 | 3 | — | — | alcohol wash; older and higher than the 2026 figures above; spring and summer only |
Sources
- Honey Bee Health Coalition, Tools for Varroa Management, 9th edition (2026).
- Ontario.ca, Treatment options for honey bee pests and diseases in Ontario (updated 30 October 2026).
- Perennia / ATTTA, Summer Disease and Pest Monitoring in Honey Bees (2016).
- OBA Tech Transfer Program, Varroa Mite: Sampling and Monitoring Infestation Levels (2012): sample size.