Pertusaria albescens

Description:

Crustaceous lichen. Thallus pale greenish grey to grey, often zoned at the margin, surface with often abundant, often (but not always) clearly delimited, round soralia that lack a bitter taste (compare with P. amara); apothecia rare.

Habitat:

Widespread on bark of deciduous trees, rarely on other substrates. Spotted on the trunk os a chestnut tree

Notes:

Camera Model: NIKON D300. Exposure Time: 1/60 sec.; f/32; ISO Speed Rating: 200. Focal Length: 90.0 mm. Flash fired