I am enjoying the recent exchange of emails on the subject.  As Allen has
pointed out, the need for winter wraps or for winter packing varies a great
deal with location.  Some beekeepers will not have an experienced beekeeper
to use as a mentor, and it is particularly important that these choose the
right 'solution' for the hive top.

When considering how to prepare the hive top for the winter, keep in mind
that the objective is not as much to keep heat in the hive as it is to
prevent condensation of the warm moist air from the cluster causing water to
drip onto the cluster, which will almost certainly kill the bees.

There are three basic approaches to prevent the condensation:
1.  To have some absorbent material that will retain the moisture.  This is
the purpose of the homosote boards and/or straw packing in a super placed on
top of the upper box.  Many commercial beekeepers around here use the
homosote boards.  They go on the hive around now, under the outer cover.  If
kept indoors for the summer, they weigh a pound or two each.  When they come
off in the spring they weigh 5-10 pounds!
2.  To have some insulation under the outer cover so that the warm moist air
does not come into contact with a cold surface, which is what causes
condensation and precipitation.  I have seen beekeepers use 2" sheet
insulation, and have experimentaly used it myself.  I do not know anyone who
uses this every year, and I do not as I found that sometimes it gets so cold
(in this climate) that the insulation is ineffective.
3.  To create a top opening so that the warm moist air escapes the hive and
never gets a chance to condense and precipitate.  This is what I do.  I rip
cedar wood shingles into 1" shims, and put shim under the inner cover
so the butt end (3/8" thick) creates an opening.

Hope this helps,

Lloyd

             ***********************************************
The BEE-L mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software.  For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html

Access BEE-L directly at:
http://community.lsoft.com/scripts/wa-LSOFTDONATIONS.exe?A0=BEE-L