Why Are Mushrooms Invading Wyoming Lawns? Are They Poisonous?

It's not uncommon to discover an errant mushroom or two cropping up on my lawn when warmer weather rolls around. Typically, I discover the little invaders while gardening. Usually, they aren't much of a problem - just a stray mushroom or two trying to take root.

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This year, I'm dealing with a mushroom army. An entire legion of fungi sprouted up in my front and back yard seemingly overnight. And it's not just me. They are everywhere - the Laramie County Library's boulevards, Cahill Park, and the rolling lawn of the Capitol Building. Mushrooms everywhere.

As an owner of two dogs and a very curious child with a penchant for sticking random things in their mouths, this concerns me. I know enough about mushrooms to know they can be dangerous. I had to wonder - why are all these mushrooms cropping up on Wyoming lawns? And are they dangerous?

Mushrooms Are Invading Wyoming Lawns - Here's Why.

We've been getting so much moisture here in Wyoming since Spring kicked off it's started to feel like a swamp around here. It's humid. It's muggy. It's wet.

According to Professor Steve Miller, a botany instructor at the University of Wyoming specializing in fungi ecology and symbiosis, mushrooms "love" these conditions.

He's been getting quite a few inquiries about mushrooms himself - particularly from folks wondering if the mushrooms are harmful to pets, animals, or children. His answer was pretty simple - some mushrooms might be harmful, some might not. The trouble is that you have to identify the kind of mushroom you're dealing with. For all you know, the mushrooms growing in your yard could be a delicious addition to a salad...or a deadly poison. "Some of them might be harmful while others are not. Specifics on each mushroom are required," explained Steve.

What Kinds of Mushrooms Grow in Wyoming?

Note, you should NEVER eat a mushroom unless you 100% know what kind of mushroom it is. Many toxic mushrooms look like benign species. It can be a deadly mistake to mix up a poisonous mushroom with an edible one.

Non-Toxic Mushrooms That Grow in Wyoming

• Ringless Honey Mushroom - Golden in color. Edible when cooked. Considered Parasitic Fungi and kill trees.
• Field Mushroom - White or brown in color. Edible. They grow on dead vegetation (e.g., dead leaves, decaying tree stumps, etc.)
• Morels Mushroom - Brown. Morels are edible and beneficial to the environment.

Poisonous Mushrooms That Grow in Wyoming

• Destroying Angel Mushroom - White coloring. They thrive near woods.
• Fly Agaric Mushroom - White stem with a red cap. Can cause hallucinations (avoid eating it.)
• Haymaker Mushroom - Brown in color. One of the most common kinds of mushrooms in Wyoming lawns.
• Deadly Webcap Mushroom - Light brown color. Grows near trees.
• Deadly Galerina Mushroom (Funeral Bell Mushroom) - Brown and gold colored. Grow near dead trees.
• False Parasol Mushroom (Vomiter Mushroom) - White/fleshy colored. Common in gardens.

For more information on mushrooms growing in Wyoming, visit the Wyoming Mushroom Society Club Reference Guide here.

Resources for Identifying Mushrooms in Wyoming:

You can always reach out to your local botanists, Master Gardiner's, or the University of Wyoming Extension for assistance in identifying plant life in Wyoming. You can also check out the Peterson Guide to Mushrooms. Or, reach out to the University of Wyoming Botany Department for assistance:

Can You Remove Mushrooms From Your Lawns?

Professor Miller doesn't have much faith in permanent mushroom removal. "Can you get rid of them? Maybe if you had millions of dollars, but I'm not even sure then. Many of them grow from dead or dying tree roots or buried wood, grass thatch, and roots or other organic matter, or symbiotically associated with trees. Studies have shown that you might be able to knock them back for a while, but they will come back."

So what should we do with the mushrooms we see popping up in our Wyoming lawns and gardens? As far as Dr. Miller is concerned, your best bet is to educate yourself and learn to live with Mother Nature's little army of mushrooms.

"My advice is to learn about the mushrooms. You have to be able to answer the question of is it harmful for yourself, and learn to enjoy them in your yard.  They can be friends that you see every year."