Hen of the Woods grow at the base of oak trees. These mushrooms are beloved by the Japanese as maitake; they also happen to be my personal favorite. They grow in large, dull brown clumps (as a polypore or bracket fungus) that look like the back of a brown hen’s ruffled feathers. The mushroom caps are attached to each other by short white stems. These mushrooms can grow to be several pounds and more than 2 feet wide. On the east coast they appear in September and October.