>> Most tree colonies I've worked with had a single entry hole.  Inside the
hollow above the colony, there is typically a dead wood core of the tree.  

Finding bees in trees is always very interesting. But one should refrain
from assuming the bees have picked the ideal home. It may be the best choice
among the few choices available. 

Living in San Diego, I once saw a colony of bees living in a below ground
cave. I doubt that was ideal, but they evidently decided it was the best
they could do. 

I often saw swarms living in bushes. I figured they simply gave up looking
for a suitable place and stayed where they were. 

pb

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