Agriculture Reference
In-Depth Information
Cover the jar with the mesh lid and store upturned in the dark at room
temperature.
After 24 hours, place the upturned jar over some white paper and hit it to dislodge
the dead mites. Count the initial mite kill.
Replace the lid and put the jar of bees in a freezer until they are dead (1-4
hours).
Take the jar out of the freezer and hit it again to dislodge any dead mites that were
not killed before. Count these.
% kill by the chemical strip = Initial kill รท (initial + final kill) x 100.
The number killed by the chemical strip = the initial kill. Add this number to the
number killed by freezing the bees (the final kill). Divide the initial kill by the sum of
the initial kill and the final kill and multiply the result by 100. This will give you the
percentage killed by the chemical strip. If this is less than 50%, the mites are probably
resistant to chemicals.
Treating and protecting against varroa destructor
Timing
The timing of the treatment is important.
Treat
your bees in the spring when large
amounts of brood provide the ideal conditions for varroa infestation. If you don't, your
colony could collapse in the late summer. Use an authorized miticide, such as Apistan
or Bayvarol (see below).
To
protect
your colony against a varroa invasion, treat it in the early autumn, after the
harvest. For this, use an organic product, such as oxalic or formic acid. This will slow
down the mites' resistance to miticides and the formic acid will penetrate the wax to kill
the mites capped in the cells.
You should usually assume you have varroa in your hives even if you can't see them.
Contact your local beekeeping association to find out what everyone else is doing and
