brown crust or patch fungi (corticioid fungi) growing on a dead tree trunk : (pix sanjiv shukla)

brown crust fungi corticioid family corticiaceae mushroom patch ecological fungus importance evolutionary diversity dead wood growing stick log bark tree leaves duff rock saprotroph organic matter nutrition host branch fungal forest health ecosystem saprotrophic recycler soil trunk coniferous fruit bodies organism decaying unedible wild texture colors microscopic structure mycologist spore granular spiny worldwide distributed