So we've probably all heard about the studies done on honey bees. If not, you can google it, there's a lot of info out there.
The trouble with bees is they are mobile. They fly. When their hive gets crowded, they swarm in search of a new home. Like the knot hole of our Maple tree. Yep, we've got bees in our trees. (OK, just one tree but that doesn't rhyme.)
We weren't home when they swarmed, but our neighbor witnessed it. It didn't take them long to inhabit our tree though and now we're stuck. You see, if we could have called a bee keeper when they were swarming, they would have gladly come to get them.
Swarming bees = good bees to capture and relocate.
Happy bees building a hive in a tree = no one wants them.
It's to dangerous, difficult, time-consuming, yadayadayada....to deal with them once they are established. So our options....cut the tree down or kill the bees.
I hate to say it, but bye-bye bees. I love my tree and honestly, if the neighbor behind us weren't so concerned for his son and wife (both highly allergic) we'd let them stay. They are happy bees. They are high enough up in the tree they don't mess with anyone, but the liability of what might happen/could happen means the bees have to go.