Question

fungus trunk maple tre   Also have on numerous other tree trunks throughout our 5 acre lot.  Have tried spraying a fungucide our local landscaper sold us, but hasn't helped.  We live in norther ohio.

Answer
Helen:

These fuzzy patches of mustard colored and gray green growths on the bark are lichens.  Not considered plant disease organisms. They are often seen on older or declining trees.  Often seen on trees and woody plants in the shade also.  Lichens will grow on fence posts and also rock.

Regards
Steve