By BOB RIGGS
Indiana Correspondent

FRANKFORT, Ky. — Two decades ago, when the reddish-brown, tick-like varroa mite was first reported in Kentucky, there was no accepted treatment beekeepers could use. The tiny invasive mites suck the blood of bee larva and from adult bees, resulting in disease, deformities and general poor health of the whole hive.
Since that time, however, the problem has been researched and well documented. Today there are several chemical and non-chemical methods that can be used to control mite damage to the hive.

During the 1990s the product Apistan was found to be an effective chemical treatment against varroa infestation. By 1999, though, there were reports of the mites becoming resistant, resulting in lost colonies.

In 2001, Phil Craft, the apiarist for the Kentucky Department of Agriculture (KDA), reported the state had experienced heavy losses of bee colonies due to widespread resistance to Apistan. At that time, he announced the U.S. Environmental Protection Agency (EPA) Section 18 approval of a new product called CheckMite.
Craft informed beekeepers that CheckMite had become the best weapon for protection from varroa mites. But by 2004, the KDA announced resistance to CheckMite was also increasing.
At the same time, the EPA had approved another weapon in the fight: ApiLife VAR was the name of the promising new mite killer.
Both Apistan and CheckMite are made in the form of thick chemical-coated plastic strips that are inserted between frames in hive boxes. ApiLife VAR, on the other hand, is a bar or tablet put in the hive.

The bar is saturated with organic oils, which give off vapors that cause the varroa mite to fall off the bee to the floor of the hive.
ApiLife VAR contains the ingredient thymol, which is a derivative of the herb thyme, and eucalyptus. Craft said it was the first of a new generation of safer, less toxic varroa combatants. At that time he began suggesting rotation of the different control agents as the most productive way to fight the resistance problem.
Craft said other applications have consequently come to market, such as Apiguard with thymol and MiteAwayQuickStrip with formic acid, to name a couple. Then just this July, he announced another new varroa mite product.

HopGuard, also organic, is derived from the hop plant. The active ingredients are natural food and potassium salt products instead of dangerous chemicals.Craft said the introduction of multiple products allows beekeepers to rotate the agents in order to reduce the resistance problem. However, he warned each application works better under particular circumstances and seasonal conditions.

He also mentioned pest management methods such as new screened hive bottom boards that keep mites from returning to the hive when they fall off the bees. Plus, there is research into bee lines that have some resistance to varroa mites.
Craig, a long-time apiarist, gave this list of beekeeping recommendations:

-Use management control (employ more than one method)
–Use screen bottom boards instead of solid wood floors
–Look into resistant bee stock

–Use scientific method to determine if varroa mite levels are high enough to require treatment

-Use the low toxic chemicals as needed (or in the fall)
“While these techniques will not completely eliminate the need to use chemical control, they will reduce it.” Craft said.