Instead of falling to the ground and breaking, some trees behave strangely when falling. Some do a 360 spin (vertically, falling through the ground then spinning into the proper place) as they fall before landing and breaking. Others "land" a couple feet off the ground then break. It seems inconsistent across tree types and I unfortunately don't have the time to play any more to test it further.
#Trees falling physics issues
tulip lichen
formal thistle
I have had them fall on me to, had to watch them to see what way they would fall, and move out of the way.