Fertile surface usually a layer of vertical tubes, of which the mouths are visible as pores on the underside of the cap or shelf. Fruiting bodies usually tougher or harder than the "normal" gilled mushrooms, being leathery, corky, or woody. But they can be quite tender while actively growing
Once grown, they do not decay easily, remaining on the substrate for months or years
They often grow on wood, although a few are terrestrial (even those are usually growing on buried wood) Fruiting body is usually a flat shelf, or hoof-shaped, protruding directly from the substrate, although sometimes it may have a short stalk.
Some forms never grow away from the substrate at all, so that all that is visible of the fruiting body are the pores.
Sometimes the pores are so minute that the fertile surface seems solid, until you look closely
Large (6-18" or more across), compoundfruiting body with irregular caps, usually right next to a tree or even surrounding it Flesh flexible, tough but not hard
Colorful furrycaps and (non-furry) pore surface, darkening to black (and bald) in age
Primarily on living conifers, although it will continue to decay them after they have been killed (standing trees, stumps, and logs); rarely on hardwoods