Shelf Fungus

Most bracket fungi that are visible during the winter are woody and perennial, adding a new layer to their shelves each year – thus getting larger and thicker.

Winter is a great time to look at certain elements that are more difficult to see in the forest when all of the trees have their leaves. One of those might be fan-shaped or shelf-like growths that can be found on the sides of trees and stumps.

These growths are actually a type of fungus called shelf or bracket fungi. Bracket fungi are related to puffballs and mushrooms, as well as other fungi. Many are woody and long-lasting in nature, while a few are fleshy and short-lived.

These fungi are non-photosynthetic, which means that they are unable to produce their own food by using the sun’s energy. Instead, these organisms get their nutrition by digesting cellulose and lignin from within the wood on which they are growing. They are an important part of the nutrient cycle in a healthy forest.

 A bracket fungus begins its life as a spore, one of hundreds of thousands produced by a mature fungus. If the spore lands on a favorable location, such as a tree stump, it sprouts tiny thread-like mycelium, which invade the stump. Mycelium cells manufacture and secrete enzymes that digest the wood. The tree’s cellulose is broken down into its simple sugar building blocks, which are absorbed by the fungus. The space vacated by the dissolved wood leaves room for the fungal mycelium to grow deeper into the tree.