This morning about 5 am we were awoken by a creaking, splintering sound and
discovered later that a large branch had broken off a large mature ash tree
at the bottom of the garden. I don't quite know how tall the tree is, but it
is big. The branch came from about half way up and at the thick end is about
10" diameter, it's about 24' long, with side branches etc. It's now covering
the bottom end of the garden.

My question is this - why should such a large branch break off? Smaller
branches have dropped off in the past, but nothing this big in the 19 years
we've been here. There are plenty of leaves on this branch and on the rest
of the tree. Is it just natural ageing, or could the tree have other
problems?

Peter.