Strangely, some tree-killing fungi are also beneficial to your health. While some mushrooms that kill trees may be medicinal, sick and dying trees are not beneficial to your landscape. Sick trees can fall and cause property damage, and the fungal infection can spread to other trees on your or your neighbor's property.
What Tree Mushrooms Signify
Mushrooms growing on or around your trees are a sure sign that your tree is weak or diseased. The mushroom fungi spread inside the tree first, clogging up arteries that carry water and nutrients, robbing the tree of what it needs to live. Once the tree is filled with fungi mycelium, the mushrooms start to emerge either from the bark, around the base or from the roots. By this time, your tree is actively dying and usually beyond saving.
Chaga is a stage of the polypore mushroom Inonotus obliquus. Also called "tree cancer," it is one of the strangest looking mushrooms you'll ever find on a tree. It emerges from the bark of birch, alder, hornbeam or chestnut trees as a crusty, black alien-looking mass. Research has shown this hideous mushroom is an effective treatment for a number of ailments, including irritable bowel syndrome, as well as both H5N1 Flu A virus and Flu B virus. While Slavic peoples use it as a traditional cancer treatment, test have not confirmed its efficacy for this use.
More commonly known as reishi, one member of this family is the deadly mushroom that causes butt rot in palm trees. Also called shelf mushroom or turkey tail, it is one of the most widely researched and respected medicinal fungi. Studies have shown it to be effective in slowing the growth of certain cancers, such as breast cancer, by significantly increasing the number of T-cells. Studies also show it to be effective in treating urinary tract symptoms in men. Proponents cite its efficacy in treating a large range of maladies from acne to vitiligo. It does have side effects and can interact with certain medications, so talk to your doctor before using this remedy.
Armillaria is a root-rot fungus whose fruiting bodies are known as honey mushrooms. These small, honey-colored fungi appear in large, tightly-packed masses. Because they grow in and attack tree roots, they can appear either at the base of a tree, or some distance away. They are used in cooking, although they are not the tastiest edible mushrooms. Their taste has been described as bitter or sour. This fungus is easily confused with the poisonous oak-root mushroom Naematoloma fasciculare, so be sure you have a positive I.D. before consuming them.
Finding mushrooms growing out of or around the bottom of your tree is unhealthy. By the time you see these mushrooms, the tree is either already dead or well on its way, and may need to come down. Your local tree removal expert--such as one from Arborcare Tree Service--can tell you exactly which fungus you are dealing with and whether you need to have your tree removed. Since the majority of mushrooms are poisonous, never consume any mushroom without consulting an expert.