There are two widely used methods to assess the mite levels in your hive.
Corex Sheet. This is a sheet which slides under a screened bottom board. Spray the corex sheet with a cooking oil so when the mites fall from the hive they stick to the sheet and can then be counted. Insert the sheet for 3 days and then remove it to count the mites. Once you have a total, divide it by 3 to get the average mite drop in a 24 hour period.
Sugar Shake. Place a few table spoons of powdered sugar in a mason jar and gently "slosh" some bees (about ½ cup) around ensuring they are fully coated. Replace the lid with #8 hardware cloth and the sugar will dislodge the mites allowing them to fall through the screen.
Below is a very general guide to determine if the colony should be treated. However, the prevailing thought is if you have a window of opportunity to treat your colony you should treat.
|Corex Sheet||5-10 mites||50-60 mites|
|Sugar Shake||3-4 mites||10-12 mites|