Freezing honeycomb protects it from wax moth damage
Contrary to rumor, comb honey does not have to be frozen before it is eaten. If you like, you can eat it warm and gooey right out of the hive.
However, comb honey is often frozen to protect it from wax moths. Wax moths—also known as bee moths, wax millers, or web worms—live and reproduce on honeycombs and can destroy them very quickly. Since freezing kills all life stages of wax moths, it assures that your comb honey will not become infested during storage.
A healthy and populous hive of bees easily controls wax moths. But hives that become weak—or combs in storage—are easy targets for wax moths. The adult moth lays her eggs on the surface of the comb or in the cracks between hive boxes. After the larvae hatch, they dig through the comb, looking for bits of pollen or the empty cocoons of bees. Because the larvae eat the pollen and cocoons—not the wax—they are seldom found in clean, new comb or fresh foundation.
To get to the food, however, the larvae tunnel through the comb and line the tunnels with silken webbing called “galleries.” As they move through the comb they open capped cells of honey and brood, tearing apart the entire structure. Depending on the temperature and environmental conditions, a heavy infestation can ruin a brood box in a week.
You can minimize the problem of wax moths in several ways.
- Keep hives strong. Combine weak hives. Populous colonies are the best defense against wax moths.
- Don’t allow odd pieces of wax comb to remain in the vicinity of your hives as these may attract moths. Collect wax scrapings and burr comb and remove them from your apiary.
- Freeze honey combs before storing. The USDA recommends 24 hours at O° F.
- Store empty combs in a cool, well-ventilated area such as outside or in an unheated building. (They must be protected from mice, however.)
- All hive openings—other than entrances—should be covered with screening to prevent the adult female moth from flying into the hive.
- Keep boxes in good repair. The adult moth may lay eggs in the space between the boxes if she senses the presence of comb. Solid contact between the boxes makes it harder for the larvae to squirm their way in.
Although some beekeepers place a chemical called paradichlorobenzene in stored boxes, this is carcinogenic and cannot be used for honey meant for human consumption. Worse, it does not kill the eggs, so when the chemical is removed the remaining eggs may still hatch. It is far better to use good management practices and skip the pesticides when at all possible.