This Wednesday, October 17th at 9 a.m EDT (real early in the west) Ohio State University will be presenting their October Beekeeping Webinar with author Kim Flottum entitled "Putting the Hive to Bed for Winter". To join in the webinar go to the Sign-in page at 8:55 a.m EDT. All of the O.S.U webinars are recorded and available at their Bee Lab or in our Beekeepers' Library in the Webinars section.
The Bee Informed National Management Survey 2010-2011 (Survey) revealed some interesting insights into winter management. Although the survey (Survey Results and Survey Respondent Profile) is new and relatively small scale it showed no measurable impact from winter preparation methods like hive wrapping or insulation but showed significant benefits from the equalization of hives in preparation for winter and the inclusion of an upper entrance. The Canadian Association of Professional Apiculturists also suggests that an upper entrance is important to vent excess moisture (The Biology and Management of Colonies in Winter). The upper entrance also provides an alternative if the lower entrance is blocked by snow or dead bees. They also suggest that it is beneficial to wrap or insulate your hives in colder climates.
The photo above is of one of my hives which is admittedly pampered. It has a screened bottom board, mouse guard, hive body insulation and wrap, insulated moisture quilt and poly (2x4 and plastic sheet) weather cover. The poly cover is mostly to protect the hive from strong southeast winds (local winter phenomena) and driving rain. Obviously your winter preparation practices will depend on your location and how many hives you have. With a thousand hives you certainly can't do what I have done above.
Barbara Bloetsher did a previous webinar entitled "Planning now for Winter Preparation" that can be viewed in the webinar section of our Beekeepers' Library here. There is also a few other webinars on wintering bees (Overwintering Bees and Getting Ready for Winter) that can be downloaded in the webinar section.
Overwintering Hives from the University of Georgia Center for Continuing Education
Enjoy the webinar. It should be good.