What It Really Means When Mushrooms Start Growing On Your Trees

Seeing mushrooms that sprout up around your property might appear to add some whimsical flare. These sometimes-colorful fungi can pop up out of the grass or elsewhere in your yard after rain. This can signify that your lawn is healthy and bursting with nourishing organic material. But what if you see mushrooms growing on your trees? Unfortunately, this may mean the exact opposite and can indicate your tree's failing health. 

Mushrooms coming out of your tree, particularly at the base of the tree, can be a sign of a fungal infection and that your tree is rotting on the inside or at the root. Diseased or damaged trees can attract fungi, which feast on dead organic matter. Fungi use enzymes to decompose the tree from the inside. Eventually, that fungi will spread throughout the tree and eventually show up on the outside as a mushroom. The mushroom is the fruiting body of the fungi. Once fungi spread through and create enough decay in your tree, it eventually causes the tree's limbs to fall off or the entire tree to fall over and die.

By the time you see mushrooms on your tree, it's usually a sign that the tree has already decomposed a good amount and that significant damage has already been sustained. Since fungi release spores into the air, they could spread to the other trees and plants in your yard by the wind, animals, bugs, or water. So, it's important to act quickly when you observe this condition in your trees.

Fungi will start to spread throughout a tree that is under distress. This distress can be caused by several reasons, including soil that is too dry due to a drought or too moist from a flood. These conditions can damage the tree's roots preventing it from getting enough of the nutrients it needs to survive. Fungi that live on the soil or the surfaces of the root will attack when the root becomes vulnerable due to sub-optimal soil conditions. 

Exterior damage to a tree can also cause fungi to invade. Exterior tree damage can be caused by holes, scrapes, or carving into a tree by humans or landscaping equipment, as well as broken, cut, or pruned branches and leaves. Damage can also be caused by heavy wind, lightning strikes, or fire. So, the best way to prevent mushrooms from growing on your trees is to prevent physical damage, while also protecting its internal health.

While you may be tempted to start hacking away at the mushrooms sprouting from your tree, it's the last thing you should do. This is because cutting them can release spores which can spread to the other trees in your yard. What you should do is contact an arborist. They will use the mushrooms to help them identify what kind of fungus is attacking your tree. 

The tree can possibly be saved if the mushrooms are growing on tree branches since an arborist can safely cut the branch to prevent the fungus from spreading to the rest of the tree. But if the mushrooms are growing at the base of the tree, the tree might not be salvageable and have to be cut down to prevent it from unsafely toppling over. An arborist will use something called a resistograph that will measure how deep the fungi have decayed the tree. This assessment will help determine whether or not the tree can be saved.