> I have a frequent "mugging" problem with yellowjackets around my hive.
[snip]
> food source.  Strong colonies drive them off, but weak bees and stragglers
> beware!
 
This was discussed a while ago on the sci.agri....beekeeping group.
A semi solution I posted was to lean a sheet of glass or perspex at
an angle on the front of the hive.  The bees, coming from inside cn
find their way both in and out, but the wasps, hornets, yellow
jakcets cant find their way in (at least thats the theory...)
Adrian.