I had the problem of the tree not falling after being chopped again today. This happened in Zone 707 at 250.34 x 329.83, it was a willow tree. When I logged out and back in, the willow tree was gone, I then cut another nearby tree with no problems. Prior to this tree, I had cut two others in the same area with no problems. I had also cut other trees in different areas with no problems. Hope this helps.