A lichen, not a group I am much good at.
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.
C. fimbriata was the Cladonia I had seen before but as that was growing on a rocky substrate I thought this (on wood) might be something different.
Cladonia fimbriata is not fussy about substrate. At a site near me it is currently growing on an abandoned woolly hat.
Lat/Lng: 51.5, -0.4
OS grid ref: TQ1583