A sticky board gives a highly inaccurate estimate of the mite load.
The hive may show low numbers if there are few mites, or if the
colony is very weak. Also, the closer the cluster is to the board,
the number may be higher. You need to do ether roll or sugar roll.
There is no universally accepted threshold for mites. Generally, if
you have mites you need to to treat. If you skip the treatments you
may lose the hives. Most beekeepers treat the whole apiary because
the mites spread from hive to hive.
Peter Borst
Ithaca, NY
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