Post by Thom on Jun 29, 2006 10:38:56 GMT -7
When doing presentations on chemical free beekeeping, I am often asked about how to store comb and protect it from wax moth with out using chemicals. The accepted means of comb storage has been to employ fumigants such as PBD, Paradichlorobenzene. Slowly the PBD crystals dissolve into a gas which is heavier than air. You are supposed to check it every month and add more crystals as needed. PBD kills adult moths, but not the eggs.
The problem with PBD is that it is a nasty, dangerous chemical. Wax, being a lipid substance, absorbs this gas. Any honey left in the wax will absorb it as well. It is always suggested that you air out your frames for at least a week before introducing them into a colony. However, studies (1) have shown that about 40% of the PDB remains in wax even after two days of airing.
So if fumigants are bad, what can we use to protect our comb from wax moth? It is actually pretty simple. All you need is a freezer. First, start with an empty box. Place your frames into a freezer for the proper time and temperature listed below.
Remove the frames when the recommended time has passed, place them in the empty box and seal them. Make sure a moth can not make its way into your frames after you process them. Have your boxes placed on a flat surface like plywood or hive cover. Tape over any vent holes or cracks in the boxes. Tape the joints where one box rests upon another box. Check the frames in mid-winter to be sure there hasn’t been a moth invasion that somehow got by your barriers.
Below is the list of time and temperature that are effective against wax moths and their eggs. Leaving frames in for a longer period will not harm will not harm your wax, so if you forget that you have some in the freezer, no harm done.
(1)Freezing comb will protect against all stages of the life cycle. The minimum temperature and exposure time to destroy all stages of the wax moth are: 20°F (-7°C) – 4.5 hrs., 10°F (-13°C) – 3.0 hrs., 5°F (-15°C) – 2.0 hrs.
Warming the comb to 115°F (46°C) for two hours is also effective but be careful. Wax starts melting above 120°F.
Reference: (1) www.msstate.edu/Entomology/beenews/beenews0705.htm
The problem with PBD is that it is a nasty, dangerous chemical. Wax, being a lipid substance, absorbs this gas. Any honey left in the wax will absorb it as well. It is always suggested that you air out your frames for at least a week before introducing them into a colony. However, studies (1) have shown that about 40% of the PDB remains in wax even after two days of airing.
So if fumigants are bad, what can we use to protect our comb from wax moth? It is actually pretty simple. All you need is a freezer. First, start with an empty box. Place your frames into a freezer for the proper time and temperature listed below.
Remove the frames when the recommended time has passed, place them in the empty box and seal them. Make sure a moth can not make its way into your frames after you process them. Have your boxes placed on a flat surface like plywood or hive cover. Tape over any vent holes or cracks in the boxes. Tape the joints where one box rests upon another box. Check the frames in mid-winter to be sure there hasn’t been a moth invasion that somehow got by your barriers.
Below is the list of time and temperature that are effective against wax moths and their eggs. Leaving frames in for a longer period will not harm will not harm your wax, so if you forget that you have some in the freezer, no harm done.
(1)Freezing comb will protect against all stages of the life cycle. The minimum temperature and exposure time to destroy all stages of the wax moth are: 20°F (-7°C) – 4.5 hrs., 10°F (-13°C) – 3.0 hrs., 5°F (-15°C) – 2.0 hrs.
Warming the comb to 115°F (46°C) for two hours is also effective but be careful. Wax starts melting above 120°F.
Reference: (1) www.msstate.edu/Entomology/beenews/beenews0705.htm