Just some great links to help remind everyone to keep track of their mite numbers.
What - How - When - Why - Watch!
What - You are looking for how many mites per 100 bees. A quote from Article: "Test For Varroa" that is of interest to us northern rural farm & forest beekeepers: “Thresholds are regional since they largely depend on how long the brood rearing season is and thresholds are dependent on the type of beekeeper. The colonies of an isolated hobbyist in the north could maybe withstand a 10-12% infestation, but colonies of a migratory beekeeper in Texas may need to use the 3% infestation threshold.” Katie Lee – Bee Informed Partnership
How - I use the "sugar-shake" method to TEST. Caution: don't confuse the sugar shake method TEST with treating bees for varroa using powdered sugar in the hive. This is no longer a respected way to effectively or safely knock mite counts down in your colonies. Use powdered sugar to TEST not treat. There are too many variables using it to treat and too many risks you may actually kill your colony. I have killed two colonies as a result of treating with powdered sugar, even sugar I powdered myself that did not have corn starch in it. Search for an article about this treatment method well researched by respected scientist Jennifer Berry.
Now as for TESTING with sugar - Phil Gavin of Portland's Honey Exchange is a northern URBAN beekeeper looking to treat at lower mite counts that the rural beekeeper; but he does a great job of showing how to test for varroa with the sugar shake method in this YouTube video: Sugar Shake Test For Varroa Mite
When - Late summer, early fall is when the phoretic (mites outside capped cells, on the bees) mite count is highest. Brood rearing in the north slows down and mite populations begin to reach their peak.
Why - So you have confidence in your management practices, are not guessing about the health of your bees, and don't sound irresponsible when you talk to others about your treatment free survival colonies. Not all will survive. You may still find yourself guessing about why but records can reveal all sorts of insights about your colonies that can often seem unimportant when your bees are thriving.
Example: This is the most inspiring example of successful treatment free management and the best done report of UK beekeeper Ron Hoskins working with a scientist to discover why his bees survive their mite loads:
WATCH THIS YouTube: "Honey Bees Able To Immunize Themselves Against Varroa"
Wishing all your bees a great fall nectar & pollen flow!