Earlier this year my Dawn Redwood was hit by a late frost and the new foliage was damaged, as the tree is very strong it had started to recover, until I looked closely. The top was looking very flat and some of the new leaves were broken.
The cause turned out to be Pigeons sitting on top of the tree. I have now moved the tree into the shade house and it is looking better.
Even after just a couple of days the foliage is standing up again.