Mushrooms Growing at the Base of Maple Tree

I have about a 30 year old maple tree and over the past few years I have a rather large mushroom growing on the base of the trunk. Each year the mushroom is bigger. It even grew back after treating it with Round-up. Now there are two that look like elephant ears stacked one on the other. Are these overly dangerous, I have children? Secondly, is there anything I can do to eliminate these without harming the tree?

The growths on your maple tree are the fruiting bodies of a shelf fungus. These wood rotting fungi feed on decaying wood inside trees. Round-up is a plant killer and will not kill fungi. Though some species of shelf fungi are edible leave the harvesting to the experts. Encourage your children to look but not eat these interesting structures. Shelf fungi can shorten the life expectancy of your tree. Keep in mind this fungus is a secondary problem moving in after something damaged the tree and started the decay. The location and extent of the rot will determine the impact on the tree’s health and longevity. Consider hiring a certified arborist to examine the tree. They have equipment and the expertise to determine the extent of damage and if the tree poses a threat and should be removed.