Happening in Darnestown too
A different kind of surface lichen.
Seneca Stone Mill in 2021. It’s worse now in 2025.
https://www.google.com/maps/place/Seneca+Mill+and+Quarry+Ruins/@39.0698825,-77.3466562,861m
Happening in Darnestown too
20 miles northwest of our nation's capital
https://www.google.com/maps/place/Seneca+Mill+and+Quarry+Ruins/@39.0698825,-77.3466562,861m