They swarmed off.

When the willow fell, it was full of bees and honey.  Just hours later the new hive was set in place.  Everything was going well.

The hive was gaining popularity for a few days.  

Then the wasps got curious.  And then the hornets.  We were going to move the hive that day.  Walking back in from the field, we heard the noise.  We saw the cloud.  Then they were gone.

The wasps and hornets can clear honeycomb in minutes.  Lovely honey, dripping and full of yum is now left empty.

I can only assume that the bees got fed up with those pesky wasps and hornets.  They all agreed to find a new home.