White powder on an old plum tree bark. Whitish crustose lichen.
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.
Its not lichen spores as those can only be seen with a compound microscope. It might be a Lepraria species but its not possible to be sure from the photo.
Not all species of lichen are fertile - some reproduce vegetatively by means of isidia or soredia.
it might be Lepraria incana.
Lat/Lng: 49.6, 11.1