Native to the temperate zones, maple trees (Acer spp.) are one of the most widely-planted deciduous hardwood trees in public and private landscapes. They are long-lived, and most varieties have an exceptionally bright, scarlet-red fall color. The sugar maple (Acer saccharum) is the source of sap boiled down into the popular maple syrup.
Found on sugar and red maple as well as beech trees, Inonotus glomeratus is a fungus that infects branch stubs and wounds on the stem, which are the primary entry points. Once the decay advances, a thick, sterile mass of tissue spreads over the wound area or branch stub. It then turns black, crusty and cracked and is irregularly shaped with raised margins. Although there is no cure, removal of infected specimens and maintenance of healthy, wound-free trees will control its spread.
Oxyporus populinus forms a white fruit body with a shelflike appearance, usually with moss growing on top of it. It is most often found near the base of infected maple tree trunks. Oxyporus populinus fungus is usually in or close to cracks or wounds in maple trunks. The second part of its Latin name "populinus" means "inhabiting poplar trees," but the fungus most often infects healthy maples. One of its common names is "mossy maple polypore."
Caused by the sulfur fungus, Laetiporus sulfureus is also called "brown heart rot." It affects living trees as well as dead ones. It enters its host through bark wounds and the stubs of dead branches. Initial symptoms include bark that is slightly depressed or cracked near dying branches on the tree. Clusters of sulfur-yellow to orange conks appear in fall and become white and brittle as they age. These conks do not normally appear until the tree has extensively decayed over many years.