There has been much discussion as to the best temperature of the cellar
during the winter. Commonly it is stated that a temperature of 40° to
45° F. is best, but this is colder than usually is best for the finest
results. A temperature below 40° F. is invariably bad for the bees, and
a cellar in which the temperature goes as low as freezing is not a fit
place for bees.
It has been found by the authors that bees do the least amount of work
when the temperature of the air immediately surrounding them (inside
the hive) stands at 57° F. This is, therefore, the temperature which
the beekeeper should bear in mind, rather than to lay too much stress
on the temperature of the cellar itself. The place for a thermometer
in the bee cellar is inside the entrance of a good colony where it may
be read easily by simply pulling it out. A chemical thermometer is
best for this purpose, and it should register 52° F. or more inside
the hive entrance. In order to have the right temperature within the
hive it usually will be best to have the temperature of the cellar at
about 50° F. or slightly higher. As will be shown later, however, it is
quite possible to have the right temperature within the hive when the
temperature of the cellar is a few degrees lower than that stated.
If the beekeeper will pay attention to the temperature of the interior
of the hive he will find that in colder cellars it is desirable to give
the hives some insulation to conserve the heat generated by the bees
in much the same way that this heat is conserved when bees are packed
outdoors, although the amount of protection will be much less. In a
cellar where the temperature falls to 45° F. it will be found best
to have the covers of the hives sealed on tightly and the entrances
reduced to 3/8 inch by 2 inches. In a cellar with a temperature of 50°
F. or more the entrances may be left open the full width of the hive.
If there is a tendency for the temperature to fall to 45° F. or less,
the tops of the hives may be protected by cushions of chaff or other
materials placed at least on the top of the uppermost hives, for each
of the lower three hives is protected somewhat by the one above it.
It will be impossible to maintain the temperatures recommended unless
the cellar is built in the way described, or in some other way by which
the cellar is equally well insulated. It is impossible to maintain an
equable and high temperature in a cellar the walls and ceiling of which
are exposed to the outside air.