>Just because it is convenient I generally leave a bait hive in the beeyard. 

Larry, I am seeing here from the posts that many
claim a fair amount of success from 'bait hives' which
I am assuming are placed at or near ground level.
I myself have had success with empty hives in the 
yards at ground level.

I have also heard many complaints in the past 
about 'elevated swarm traps' not working well
in a beeyard. Many will say, the swarm landed 
on the trap but did not enter.

A main reason why elevated traps tend to fail
in beeyards is because the lure 'in this case' acts 
as a 'settling pheromone' which encourages the 
swarm to land 'on the trap.' With a swarm remaining 
in bivowac on the exterior of the trap, it  can have 
the effect of eliminating the trap as a potential 
nest site.  Elevated traps might be better placed
at a small distance further to help prevent a 
swarm from bivouacking on the trap.  IMO

I suppose I would be a proponent of using bait
hives at 'ground level' in a bee yard because,
by its position, you would more likely be targeting
a swarm in bivouac, actively searching for a void.
I expect as always that there are exceptions.

Best Wishes,
Joe Waggle
http://pets.groups.yahoo.com/group/HistoricalHoneybeeArticles/
"A Hoax.- The account furnished by Captain
French, of the Moslem, of an attack by a swarm
of natives, upon the ship Argo, of Boston, while
passing down the Hoogly, is pronounced by the
Boston Daily Mail to be a hoax. The swarm
of natives was a swarm of bees, which were
repelled by the cook."
-1843, Milwaukee, Wisconsin

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