Hello Keith,

> I perused the archives and at one point someone asked if one should use
> one or two queen excluders to separate queens in a two queen hive.  I
> could not find the answer to the question and was curious to know what
> others do.

I use only one and I have never seen two used. I have read  research saying
queens can not give a lethal sting through an excluder. I did see a picture
in the American Bee journal of two queens fighting through an excluder.

I have heard opinions expressed that with one excluder the queens will spend
time on the excluder across from each other. I have never found this to be
the case but suppose it happens on rare  occasions.

If you use a   double screen at the start then I do not believe you would
have a problem. Then switch the double screen for a single excluder . We
then remove  the excluder all together when the extra brood will emerge to
late to help gather a crop and be a liability to the hive with the extra
honey consumption.

Strong two queen hives fall over regularly, forage out farther and can be
quite nasty on days in which all bees are home and bored. Good luck!

Sincerely,
Bob Harrison