Much discussion on this subject recently and it is clear that no one is certain of the best method, if there is one. A lot or a little, half way, top,bottomor both, beekeepers try them all and most of the time the bees survive. When one considers the range of climate from the tropics to the Arctic there can hardly be one best method for all. Some years ago a well known beekeeper, Bernard Mobus, NDB and Beekeeping Adviser for Scotland, wrote a series of articles titled Damp, Condensation and Ventilation in the Beekeepers Annual for 1988,89,90. These covered some 32 pages of small text and I was so impressed I wrote to him suggesting he made it into a book because ventilation was such an argumentative subject. Unfortunately he declined and shortly after retired to France. We all know that in nature bees do not approve of top ventilation and this was how beekeepers kept them for hundreds of years. Only with the arrival of the modern hive did beekeepers start thinking about it. With the approach of winter bees seal down the cover board with propolis and if any feed holes are covered with gauze that is quickly sealed as well. They are telling us quite clearly they do not want it. In spite of that we see the advice to raise the cover board by one eighth of an inch or make holes or slots in other ways. That gap all round a Langstroth hive, 16.25 by 20 inches, tots up to a chimney of three inches diameter. A little arithmetic will show that this is equivalent to a hole in our bedroom ceiling some three feet by three feet,open to atmosphere. Extra blankets needed. In any hive exposed to winter gales, assuming a bottom entrance, such a chimney must cause a lot of heat loss, so increased food consumption. Back to Mr Mobus. His researches and those of others led him to the following conclusions. In a climate such as in Britain with a distinct winter where the queen stopped laying and the bees clustered for long periods there was an optimum sized cluster, 9000 to14000 bees for successful wintering. Large stocks and small ones had extra problems. No top ventilation but the cover board should have extra insulation. Plenty of bottom ventilation, preferably a hole in the floorboard around a foot square with suitable screening against predators. With regard to the last point I have vague memories of some experiments many years ago where it was shown that bees wintered quite happily without floorboards as long as the hole was suitably screened. Personally I have not yet got around to cutting holes in my floors. Hampshire has a more gentle climate than Scotland. All my bees have no top ventilation. Those outside have full width entrances, but with anti-mice screening, 16 or18 inches by one inch. Those in the beehouse have around 27 square inches. They all seem quite happy with it. Happy New Year to all and thanks to all those regular contributors. May the letters keep coming. Regards Sid P. _________________________________________________________________ Sid Pullinger Email : [log in to unmask] 36, Grange Rd Compuserve: [log in to unmask] Alresford Hants SO24 9HF England