Foliose lichen on ash trunk. Dark brown lobes. Lobes obscured in places with greenish fuzz (isidia?). Possibly Melanelixia fuliginosa.
Caution: Do NOT use iSpot to identify fungi to eat!
Some fungi are very poisonous so a mistaken ID could have serious consequences.
No interactions present.
In my ID above, under notes, for "glabrata" read "glabratula". I must stop doing that.
Thank you for your help in the identification and for the extra information that the group of species is now in the genus Melanelixia.
It was after you and other contributors pointed out a Melanelixia sp. that I hadn't registered at all in a photo I posted of Evernia prunastri that I became aware of the dark olive brown colored lichens!
Lat/Lng: 52.3121, -0.319
OS grid ref: TL146695