Mature Ash fails due to butt rot

The past day or two in the lakes has brought stormy weather as hurricane Katia sweeps across the atlantic. I was recently called to a tree failure in a park, where a large mature ash tree had failed at the butt and had balanced itself precariously on its branches a good six foot off the ground. Luckily the tree failed on the edge of the park which has relatively low usage apart from local dog walkers.

Clearly on inspection 85% to 90% of the stem was decayed with only 10-15% sound wood remaining. The tree had a full crown with very little deadwood. I would imagine this tree had been suffering from decay for probably about ten years due to the circumference of the stem and could no longer produce enough expansion growth in the stem to compensate for the weakness caused by the decay.

A good example of a tree failure that could have been much worse, and could have easily been picked up with a routine tree survey.