When I was little one of my family’s yearly trips was to Redwood National Park in northern California, where we stayed for about a week camping. When we would hike through the forest I would always come across mushrooms and want to take them back to our campsite and cook them with dinner, I did not understand that not all mushrooms are edible and it is very easy to pick one that if eaten would make you seriously ill. So today, I thought I would take a little trip down memory lane and look at some poisonous and edible mushrooms and help show you guys which ones you should avoid in the wild.

Now, I’m sure not all of us are official mushrooms foragers. So when it comes to “rules” for avoiding poisonous mushrooms here are some good ones that apply:

  1. Avoid mushrooms with white gills, a skirt, or a ring on the stem and a sack (called a volva) on the base. You may miss out on some good, edible fungi, but it also means you will be avoiding the hallucinogenic and deadly mushroom members of the Amanita family.
  2. Avoid mushrooms with a red cap or stem. Again, you might miss some edible ones but it’s better to be safe than sorry. They may look pretty, but they could very well be deadly.
  3. Don’t consumer any mushrooms unless you are 100% sure of what they are. It is by far the most important rule when it comes to mushroom foraging, especially if you are new to the hobby.

It’s best to educate yourself on mushrooms in general before heading out into the wild, you can check out this blog post for some more in-depth tips on foraging. But here are some key identifying features of certain poisonous mushrooms.

Agaric Mushrooms

You should be careful when identifying these mushrooms because the poisonous ones look very similar to their edible counterparts. Agaric mushrooms have pink to brown gills under their white cap and have a stout stem with a skirt. To tell if an Agaric mushroom is poisonous you should bruise the cap, if it stains pale yellow, pink, or red it is probably edible. The key is to smell it; edible Agarics smell pleasantly of mushroom with maybe a hint of almond, while the toxic ones will smell of Indian ink or iodine, just generally chemically and unpleasant.

Boletes

Boletes are a family of mushrooms that don’t have gills, but sponge-like pores that generally flower from thick, stout stems. There are two ways to make sure your bolete is toxic. First, if there is any red anywhere on the mushroom (cap, stem, or pores), treat it as poisonous. Second, you can cut it in half vertically. If the flesh immediately or rapidly stains blue, treat it as poisonous.

Milkcaps

These guys are called milkcaps because they excrete a milky substance from their gills when they are touched or damaged. This “milk” can be very acrid and/or hot so unless you know your Milkcaps or can eat hot chilies raw, don’t taste it. Most Milkcaps are toxic so until you know which individual mushrooms in this family are edible, stay away from fungi that leak from the gills. Always make sure to look at more than one mushroom when you’re checking for “lactation,” because older milkcaps tend not to leak as much as younger mushrooms.

Russulas

The Russulas have very brittle gills and stems. There are many different kinds of Russulas, some poisonous, some delicious, and some that just don’t taste all that great. A good test for edibility is a taste test; cut off a very tiny amount and place it on your tongue, if it burns like a chili it means it’s poisonous. However, this should only be attempted when you are absolutely certain you have a mushroom from the Russula family.

Amanitas

One of the most famous poisonous mushrooms, the Death Cap, is in the Amanita family. This means when you have found an Amanita mushroom you need to be 100% sure that the mushroom you have found is edible, there is no taste test for this mushroom. All members of the family have white gills and spores, but more importantly, most grow from a sack-like or bulbous structure that can be hidden by soil or leaves; you may have to get your hands dirty to check the base.

Mushrooms are great on pizza, in pasta, and many other dishes, but the consequences of eating a poisonous mushroom are not worth it. Only about 3% of known mushroom families are poisonous, but symptoms can vary from gastrointestinal discomfort to liver failure and death.

Acute liver failure from mushroom poisoning is relatively less common, but it does happen. Two of the most notable deaths are Pope Clement VII who died of accidental death cap poisoning in 1534 and possible Roman Emperor Claudius in 54 CE. Nowadays, a majority of mushroom poisoning cases happen because an amateur mushroom hunter or new forager misidentified a mushroom.

The most common signs of mushroom poisoning are nausea, low blood pressure, vomiting, abdominal pain, and diarrhea. Symptoms can be delayed for 6 to 24 hours and many survivors of mushroom poisoning recount feeling better for two to three days before relapsing with liver and kidney failure. If you have consumed a mushroom that you think might be poisonous you must immediately seek medical assistance; there is no specific drug to treat mushroom poisoning so doctors treat symptoms as they appear as well as with aggressive hydration via IV fluids.

Given the high risks of mushroom poisoning, it’s smart not to consume mushrooms that have not been collected by someone with extensive knowledge of wild mushrooms. Mycology friends recommend you do not consume any wild mushroom that hasn’t been identified by an expert because washing or even cooking poisonous mushrooms won’t make them less dangerous. “If there’s any doubt, throw it out.”

Mushrooms can be great for your health and wellness, but without proper knowledge when foraging, they can also be very dangerous. There’s no need to worry when buying mushrooms sold in grocery and specialty stores because these are ensured to be safe, these rules apply when you or someone you know has foraged for mushrooms personally. I hope this blog post has been helpful and again, check out our blog post for some more foraging tips if you’re interested in finding your mushrooms!