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http://www.honeybeeworld.com/diary/2011/diary112011.htmReport from year 2011. Very strange writings. Very strange.
A picture text: Active bees in an auger hole in an EPS hive. The temperature outside is minus twenty Celsius. The frost mustache shows that the bees are expelling moisture from the hive through the hole.
Bees are not active in 20 C. They surely are in cluster. If a big colony has been packed for winter too tight, it will be active and will die for starving.
I do not know who is this guy who just learn to use poly boxes. He found that hives are too air tight.
He had not got teaching what to do with insulated hives.
Only difference in poly hive and in wooden hive is that wood soaks water into the wall and poly hive leaks all condensation onto floor. Insulation is ofcourse a difference. Insulation value of 10 mm polyurethane is equal 4 inch dry wood.
The floor may be a mesh floor or solid floor. It may be a mesh floor whick will be closed for winter.
Europe has used polyboxes in commercial level 20 years. It have had mites too 20 years.
Biggest beeyard what I know in Finland is 3000 hives. There are several nearly 1000 hive farms.
Mite problem is well under control in Europe. Good advices we got almost 10 years ago how to do to Apistan resistant mites.
It is better that Canadian come to Germany to see how they nurse bees in poly hives and what they do to mites. There summer has perhaps the same lenght as in Canada.
Denmark has very advanced beekeeping too. Sweden and Finland have longer winter and shorter brood period than Canada.
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