Tree Life

It seems to be all trees just now. I took this picture in Doune ( near Stirling). It was cold, starting to rain, and although Doune is lovely and surrounded with lovely views I had none of those. I was hemmed in and could only see the birch wood round the Doune Ponds. i'm not even sure if this qualifies as moss or lichen or what?*



* To answer my own question I now think it is a lichen called......wait for it....Oakmoss!