White Splotches (Lichen maybe?)

White Splotches (Lichen maybe?)

Observation - White Splotches (Lichen maybe?) - UK and Ireland. Description: A small stand of ash where I walk my dog is covered in large white splotches on the bark. I am about to try the OPAL air quality survey and wondered if it was an early stage of a lichen?

A small stand of ash where I walk my dog is covered in large white splotches on the bark. I am about to try the OPAL air quality survey and wondered if it was an early stage of a lichen?