Allen Dick asked:

> *  Is a bottom entrance necessary?  Some of us have auger holes in the
>    brood boxes.  Would they suffice for entrances?

I dunno about this one.  I have not even thought of eliminating the
bottom entrance.  In fact, my bottom (screen) boards have their
openings on the long side of the (US-style) hive, which makes
for a larger than normal lower entrance.

I took this approach simply to allow one to stand behind
the hive while working with the frames "full on" rather than
sideways.  (Yes, it means that we must make our own
entrance reducers, but that's easy.)   Clearly, one needs a
strong hive to defend a larger entrance, but it has not increased
robbing in my experience.

> *  Does debris build up on the screens?

Yes, and cleaning is an issue that has been ignored by every
commercial vendor of every screen board I have seen for sale.
(A deplorable example of fuzzy thinking, in my view.  Do the
folks that "make the sawdust fly" even keep bees?
Sometimes I wonder...)

See my prior post of today, "Re: Varroa control and screen size"
for a verbal description of a screened bottom board that allows
removal of the screen for cleaning.  If I can build them, anyone
can.

> Is there wax or dead bees after winter?

In the past two years, I have seen dead bees pile up, and wax
scraps pile up, but again, a removable screen allows one to:

a)  Pull out screen

b)  Know that objects larger than screen slot are knocked
     off screen onto tray placed in the sticky board slot
     (which is below the screen, of course, and would be
     the old bottom board in the case of the most common
     varroa screen sold, which sits on a backward-turned
     bottom board).

c)  Clean screen or replace with a pre-cleaned screen

d)  Get on with more important issues

> Or do the bees seem able to make everything fall
> out the bottom?

No, I have not seen this.  Anything larger than the mesh
size appears to be carried out the front entrance (which
may be the only advantage to a front (bottom) entrance,
in that it makes this work easy for the bees.

> *  Has anyone noticed any adverse effect on spring build-up?

In spring, I convert to a "half screen", where the screen board
is covered by 1/4-inch luan plywood at the front half of the hive,
and open screen at the rear half.  The intent here is to allow the
queen to start laying more and longer at the front of the hive,
hoped to be warmer due to the heat of the sun on the front of
the hive.  The reduction in airflow at the front is hoped to keep
the front few frames warmer that much longer every day.

Ventilation at the top of the hive is also "at the rear", due to
a modified inner cover with no center hole, and vents at
the corners, with the front vents covered in spring

I have no comparison of "with" and "without" to offer, but I
was surprised to find a gentleman demonstrating dual-queen
hive manipulations at the summer Virginia state beekeepers
meeting who had worked up a very similar set-up to mine.
(Hive turned 90 degrees, and no screen in the front in springtime)

He has done this longer than I, and spoke firmly and with
certainty that this was a positive improvement.  I am not
so certain, so I would defer to him (I'll look up his name, if
anyone wishes to contact him).


        jim

        farmageddon