Lichen on top of external garden wall facing onto street
No identification made yet.
No interactions present.
These white, immature crusts on urban walls are very difficult or impossible to name I'm afraid. Chemical tests may sometimes help, but often not.
It could be young Aspicilia contorta, but this is just speculation.
Lat/Lng: 51.7841, -4.0469
OS grid ref: SN589114
On top of external garden wall facing onto street