"Bait hive".

Darn it. Why did I get stuck on "swarm trap". I'll search again.
But, Michael, thank you very much for the input. I think you've helped me see the possible folly in my plan. I didn't really know how to proceed and I had read bits and pieces of what you've told me in my searches.
I wish I had pics that I could show you. I really don't think the cone screen deal will work for me either. The shape and location of the hole in the tree is really irregular. I'd have to make a failry large cone and secure it to the tree with about fifteen bajillion staples. Also, if I would need to set my bait hive "300 yards or so away", well, let's just say that in this setting, 30 FEET would be on the next neighbors property

100 yards would be five houses down...
The only promising thing from this was that the guy called me back to say that a "cloud of bees" had formed in his yard and a cluster had formed in a bush. But within a couple hours, they were gone and there was still many bees around and in the original tree. It seemed that they had swarmed out and gone back the same day (the weather turned chilly and cloudy, maybe that forced them home prematurely). Thinking that they might be wanting to swarm out, I was hoping to provide them with a bigger, hopefully better home. But it would have to be within 30 feet. (I think the guys back yard is about 60 x 60 square.
I think I like the sound of the lemongrass essential oil. I'll check with some local health food/specialty food stores here.
This time of year, a lot of folks are planting new shrubs and stuff. Would the fiber buckets that roses come in be large enough to make a bait hive out of? I think the ones I have are only about a gallon each. I could fit a lid on top...
Thanks again!!! John