According to the data in Botanical Encyclopedia, wood rot fungus is the mycelium and fruiting body of edible fungi such as mushrooms and auricularia, or the fruiting body of medicinal fungi such as Ganoderma lucidum and Poria cocos. The wood rot fungi on the stump take soluble substances in wood as nutrients. In a suitable environment, the mycelium of wood rot fungi maintains life activities by absorbing soluble substances, and secretes enzymes to decompose wood fiber tissue. The organic matter in wood is decomposed by mycelium as a bridge and absorbed and utilized.