Like all fungi, bracket fungus likes a damp environment and tree bracket fungi attack the hardwood interior, and therefore, the structural integrity of the tree and are the cause of white or brown rot.
Luckily these appeared in a damp spot next to my garden path amongst some rocks and were not near any of my trees. Make sure the bases of trees don’t stand in water. As soon as the infection is noted, removal of the bracket fungus shelves will at least prevent the spore release that may infect other trees. The good news is that these fungi attack the old and the weak and often occur after a tree is damaged by man or nature and play an integral part in the decomposition of wood.
Standard English Name(s): bracket fungus, shelf fungus, tree fungus, conk
Scientific Name(s): various species of Fomes, Fomitopsis, Ganoderma, etc.