I saw this exchange in rec.gardens on the net, and found myself wondering.
(I pointed out that carpenter bees are solitary, to the best of my knowledge,
but these sound more like something bumblebee-ish.  Hairy, black, and
colonial.)  I'd be interested to learn what these might be, as this is a new
one on me.
 
(I've tried to sooth the fears of both Bob and the original poster that
these are no "dangerous" killer bees.  I don't understand why so many people
freak out over the mere concept of bees in the area!)
 
included posting:
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> Many carpenter bees appear to have colonized the bannister next
> to our front door (the only entrance to our condo).
 
Are these large hairy black bees?  If so, I think I have a similar
problem.  A small colony has set up shop in a shelf in my greenhouse.
They have two round entrances to their hive(?) on the bottom of the
shelf.  They seem to like nectar-producing plants, and often come home
covered with pollen.  I can hear them gnawing new passages in the shelf,
and they've made quite a pile of redwood dust.  They seem to be careful
about not making extraneous openings, which is remarkable since the
shelf is barely thicker than their door.
 
At first I tried putting a glass jar over the one opening they seemed to
prefer, and after a day or so had three comatose bees in the bottom of the
jar.  They seem to be back, however.  I suspect if I persisted in the
jar trapping, I would eventually get them all, but I've been ignoring
them for a couple of weeks.
 
Are these bees dangerous?   How much of the shelf can I expect them to
remove?
 
Bob
From: [log in to unmask] (Bob Jewett)
Subject: Re: Help! Carpenter Bees!
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