In January 2014 the featured mushroom was...
Polyporus badius: Black Leg Polypore
Polyporus varius: Elegant Polypore or the Black Foot Polypore
The very common black leg polypore, Polyporus badius, is the large cousin of the very common P. varius aka P. elegans. The caps of the Polyporus badius range from 1 to 8 inches across whereas its cousin P. varius has caps that range from 1½ to 4 inches across. When mature the cap of the black leg polypore is darker reddish brown than the cap if the P. varius. The flesh of both the P. badius and the P varius is white and very thin and tough. Neither mushroom is edible due to their tough, leathery flesh.
The stems of both mushrooms tend to be white near the top and black at the foot. Often the entire stalk of P. badius is black. Both mushrooms have a white spore print. The spores are quite similar microscopically: P. badius spores are cylindrical to elliptical, spores of P. varius are cylindrical and the size of the spores is similar.
P. varius tends to grow on hardwood and conifer logs whereas the smaller P. elegans tends to grow on hardwood sticks and branches. Both species grow singly or in small
groups though occasionally P. badius grows in large clusters.
In 1997 AB De transferred this genus into the new genus Royoporus which he had described the year before. P. varius has been dropped and both mushrooms are now called Royoporus badius though I will stick to older names until there is a guidebook using keys with macroscopic descriptions and the new names derived through DNA studies.