Some fungi are scary or downright disgusting when you first encounter them. Is that dog vomit? No, it might be an aptly named slime mold, Fuligo septica. Technically not a fungus, this protist appears suddenly, much like a lawn mushroom, and disappears almost as fast. If you knew the gargantuan effort it takes to assemble this many single-celled organism, you might just leave them be to finish out their lifecycle.
Slime mold on a tree
While fungi come in a wondrous assortment of colors and forms, the vast majority are not only beneficial but necessary. They’re also beautiful! Consider the delicate banded turkey tail (Trametes versicolor) or the artists’ favorite, Amanita muscaria.
Turkey tail mushroom
Amanita muscaria
Situation Normal
Mushrooms in your lawn are not a sign of something wrong! They’re simply the visible part of a much larger network of underground mycelium, breaking down dead and decaying organic matter. Look around – is there a stump nearby? The majority of fungi won’t harm a living tree; they’re there to help with decomposing dead or dying wood, along with leaves, wood chips, branches, and fallen fruit. Mushrooms are a good sign! They’re proof the soil is alive, diverse, and rich in nutrients – the foundation of a healthy lawn and landscape.
Mushrooms growing by a tree stump
What to Do
Resist the urge to treat it and grab your phone instead. Easy-to-use apps such as iNaturalist will help you identify which mushroom is flourishing in your flower bed.
Fungicides are not recommended. The mushrooms typically aren’t causing damage, and the chemicals are largely ineffective since the bulk of the mushroom exists below ground – think multiple square feet. It’s that extensive network of hyphae throughout the soil that comprises the true fungus from which the fruiting bodies – mushroom caps – arise. They’re a natural part of spring and fall when moisture abounds and temperatures cool. As weather conditions become unfavorable, mushrooms retreat on their own, often as quickly as they appeared. You can discourage mushrooms by watering less frequently and pruning to reduce shade.
Mushroom growing in a yard
Treatment
If you really want them gone – perhaps you have a toddler or dog that puts everything in their mouth – here’s how:
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Cut or pull or mow the fruiting bodies to limit the number of spores and future mushrooms. The rest of the fungal mycelia will persist underground until conditions return for another round of fruiting – likely not for a while.
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When trees are removed, the roots persist and begin to decompose with the help of insects, bacteria, and fungi. The only way to permanently stop the continual upcropping of mushrooms is to dig out the soil containing the decaying matter 12 to 18 inches deep and two feet outside the mushroom cluster. If that seems like a lot of work, leave the mushroom powerhouses there. When they’ve done their job of devouring all that underground material, it – and the mushrooms above – will disappear for good.
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Take care to wash hands thoroughly after handling mushrooms, as even some edible types can cause irritation.
Mushrooms are a good sign. Delight in their ephemeral presence next time they make an appearance in your yard. Most are no truffle at all.