For the last couple of months I've been noticing trees around here with branches that are not just broken, they look as if they have exploded. The branches vary in diameter from as thick as a finger to as thick as someone's torso. They are all high up in the trees, above head height, some over 5 or 6 metres up. The trees vary from willow to alder to cotoneaster. The breaks are traumatic, the broken off sections of branch hang almost vertically downward. In the case of my cotoneaster, the upper surface of the branches (3) were shattered while the under surfaces were undamaged. Other branches were unaffected. It is impossible to return the branches to their original shape because the splintering has distorted the timber so much.
We have had snow but nothing so severe as to cause a large branch to break. We have had frosts, but nothing out of the ordinary.
Anybody got any ideas as to what has affected these trees in this way?