Good morning! While hiking on the Muddy Run Reservoir Trail in Holtwood PA last weekend, I noticed what, at a short distance, appeared to be fire damage on many Berberis thunbergii shrubs in one particular section of the trail, where these plants are slowly taking over the natives. Upon closer inspection, I saw that the blackened areas weren't scorch marks, but instead some kind of strange growth almost like really thick sooty mold. Each of the affected shrubs was growing at the base of a tree (unfortunately, I was unable to ID these trees, but I know that there were many black walnuts in the area), and both the lower trunks of these trees and the ground level vegetation at their bases was also totally covered. I didn't notice any freestanding Berberis shrubs that were affected. I've never seen anything like this before and am really curious to know what it might be. Thanks so much.

~ Karin