While I agree with much of what you are saying here, I believe that
there is more to most of it than meets the eye, and which merits
discussion.
I'll start with location: what seems reasonable in your locale,
won't work reliably in Northern Canada -- if at all. I've tried it.
My comments are for our locality or places like it.
> I leave the entrances WIDE OPEN,
We have often wintered with entrances wide open, but Szabo showed
that the practice reduces brood rearing in late winter. Moreover, you
just have to go out and put them on in the spring anyhow and then mice
go crazy trying to get out.
> and jack the outer cover up about 1/2" with sticks laid across the
> inner cover rim. This allows air movement up under the outer
> cover, and across the inner cover, with bee-escape hole open.
Sounds like a good plan if you don't need insulation on the hive,
like we do. The air flow at the top in this setup would be about
right.
> Dry bees with lots of ventilation and plenty of food can keep
> themselves warm enough. Soggy bees will die. That's why packing
> them up too much can have detrimental effects.
True.
But... *too much* ventillation also stresses the bees in several ways.
For one, it shortens their lives -- not a problem if you have short
winters, and secondly it increases the feed consumption noticably,
again not a problem if you have lots of food and a short winter.
> Many years ago, Dr. C. L. Farrar at the Univ of Minnesota
> overwintered a colony in two deeps (right through a typically
> frigid Minnesota winter), which went on to produce an excellent
> above-average crop the next summer. Not a big deal, except for the
> fact that the hive's sides were largely composed of nothing but
> window screen! Really! He wrote it up in the bee journals and >
> provided photograhs to prove it! Bees CAN survive the cold if
> they can keep DRY, even if that means some drafts.
What is likely not mentioned here is that Farrar ran two queen
colonies. I studied his work and built 125 hives of Farrar
equipment (medium 6-5/8" 12 frame boxes) to run hives his way when I
first started keeping bees here.
It worked well, but was a lot of work, and the custom equipment was
not something you could just order and assemble. So I switched back
to standards and continued to run two queens. After a few years, I
realised that I was getting to do twice the work, with twice the
expense and about the same amount of honey surplus as single queens,
so I went back to single queen hives. I could run more of them with
the same resources and thus did better in every way except one:
Two queen hives had made me lazy when it came to wintering. I could
just stick a vent board on the top and leave them. Most came
through fine without wrapping. The single queen hives on the other
hand suffered drastic losses under exactly the same treatment! A two
queen hive in the fall has a lot stronger cluster of bees than a
single queen hive can be relied on to have -- both in number of bees
and in condition of individual bees.
I suspect that this effect, combined with a location considerably
south of us -- with a winter two months shorter than ours -- allowed
Farrar to pull this stunt, and it was a stunt, since if I recall, he
also did work with wraps using electric heater cords to maintain
more stable hive temperatures with impressive results.
I also expect a very sheltered location was used, since wind chill
can have instant effects around here. A 30 KPH wind at minus forty
like we had for days on end here late last winter would have killed
them with great certainty. It was hard on our bees that were bundled
up because they were already into brood rearing and needed to occupy
sufficient comb to keep contact with adequate food. (Of course
window screen does actually break the wind much more than most
people realise).
> Note, too that it has been found that the bees do not try to heat
> the interior of the hive or cavity, but rather the interior of the
> cluster. The outer layers of bees actually act as the insulation
> for the center. A short distance away from the outermost layer,
> the temperature is about the same as it is outside. (C. L. Farrar
> did the research on this as well, back in 40's I believe.)
Like many things we hear repeated about bees, it is a general
conclusion reached from observations under some pretty specific
conditions. I believe that the bees do *try* to heat the whole
interior, but they 'know' when they are beat.
It is true that bees do not need to heat the whole hive in the
coldest times of the year, but they prosper when they can occupy and
control conditions in the cavity in which they live. There have
been numerous studies done in recent years that show that in the fall
(Oct., Nov., Dec.) in North America, bees have little brood.
According to Szabo, Nov. was the one broodless month. He found
brood every other month. During the low brood rearing times, the
need for a warm hive is less.
When Winter comes (Dec., and increasingly in Jan, Feb.) the bees
begin to raise brood, and their need for environmental control
increases, since the cluster *centre* reaches and is maintained at
above 30 degrees Celcius in healthy colonies if at all possible. How
large the cluster *can* be is determined by the amount of heat loss,
and this in turn is governed by the amount of air movement, as well
as the losses due to radiation and conduction.
In our climate, the minimum air flow that removes moisture and CO2 is
optimal, and any insulation that reduces heat loss from the upper
areas of the hive is essential. Moreover, windbreak, either in the
form of bushes and fences, and/or a wrap that seals random cracks and
holes is a vital necessity most years.
If air flow becomes too great, bees lose heat fast and must consume
more honey and consequently plug up with feces and wear out faster,
moreover, they may actually even have short term problems maintaining
necessary humidity in a cold dry climate, to the detriment of the
brood. Moreover, as the cluster cools, it contracts, losing contact
with essential stores and comb surface. This may not be a serious
problem in the less drastic climates where such conditions cannot
endure for long, but where every resource is precious and must be
conserved, it may ultimately be fatal to the colony. This is
particularly true of smaller and weaker colonies.
As soon as they are able, bees will take control of the interior hive
temperature, and if their home is well insulated, the cluster can
expand and cover more food, comb, and consequently more brood.
Whether this is desirable or not is a management decision for the
beekeeper since this consumes food too. Some studies I have seen
show the interior temperature in hives in some circumstances to
normally remain well above ambient in winter.
> I often place a 2"-high rim under the inner cover on the hive. It has 3-4
> half-inch diameter holes across the front. This rim gives the bees lots of
> room to migrate over the frames to keep in touch with food.
They also may cluster up there in our country, removing them from the
combs and reducing the brood covered. When the first flow hits --
which can be very unpredictable here (+/- 2 months) -- they
then waste time and energy making comb to fill this space, comb I
then have had to remove.
> The bees do consistently well with this arrangement.
That is the main thing, but it won't work here.
Regards
Allen
W. Allen Dick, Beekeeper VE6CFK
RR#1, Swalwell, Alberta Canada T0M 1Y0
Internet:[log in to unmask] & [log in to unmask]
Honey. Bees, & Art <http://www.internode.net/~allend/>
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