Edible and Poisonous Mushrooms
Mushrooms are classified into two broad categories: edible mushrooms and poisonous mushrooms.
- Edible Species
People normally have diverse reactions to the foods they ingest – this fact holds true for mushroom consumption. What may be edible for some people may not be necessarily edible to everyone. North America is known to be home to approximately 250 mushroom species. Edible mushrooms are those that pose no health issues whatsoever when consumed.
The safest way to identify edible from poisonous mushrooms is via accurate verification of their specie by an expert collector. Though books are an acceptable alternative means towards identification of edible mushroom species, it can occasionally prove catastrophic. Empirical identification methods such as smell and taste can be extremely dangerous as some poisonous mushrooms could exhibit a pleasant smell and taste.
- Poisonous Species
Poisonous mushroom species are those that cause health complications when ingested. Their mere resemblance to edible mushroom varieties has in numerous occasions confused mushroom collectors. In some cases an unwitting victim does not exhibit symptoms of poisoning immediately after consumption, but often shows up after 48 hours. Symptom severity, however, varies from case to case.
Poisonous mushrooms can lead to death within 3 to 6 days after ingestion. As such, it is very important that the victim seek medical attention immediately. Mushroom poisoning symptoms include dizziness, breathing problems, diarrhea, vomiting and dehydration. Some of the most poisonous mushroom species include the death cap mushroom, Amanita phalloides, Amanita virosa (the destroying angel), Amanita muscaria (the fly Agaric) and Cortinariusrubellus.
Difference Between Edible and Poisonous Mushrooms
Some fungi are edible while others are poisonous. Poisonous mushrooms are known as toadstools though this is not a scientific term. In ancient time, people could not differentiate between edible and poisonous mushrooms, many lives were perhaps lost by the consumption of poisonous mushrooms. Classical writings give many references in which the harmful effects of mushrooms were mentioned. There is no general rule for the identification of edible and poisonous mushrooms.
Most people are familiar with the common mushroom varieties since these are the edible mushrooms that are readily available for purchase at the supermarket and grocery. You may not necessarily go out looking for mushrooms in the wild, but many people are known to identify, collect and ingest wild mushrooms. Again, only people with appropriate knowledge and training in mushroom identification should collect and consume mushrooms from the wild.
There are so many factors one need to take into consideration when trying to identify mushrooms in the wild. In this guide, we will go through mushroom identification process regarding their habitat, spores, gills and much more.
Typically, physical characteristics (such as color and shape) are the first attributes one will notice. Upon successful examination of these mushroom traits, the identification process becomes much easier and usually straightforward.
We’ve categorized the main mushroom characteristics into four broad sections: the toxins, habitat, physical characteristics, and the smell.
The main difference between the edible and toadstool mushrooms is the toxins present in the latter. These toxins are naturally produced by the fungi, and no known mechanism of toxic removal, including cooking, canning or freezing work for mushroom toxins.
Mushroom toxins are usually sub-divided into four broad categories including.
- Protoplasmic toxins – poisons that destroy body cells, and eventually cause organ failure.
- Neurotoxins – compounds that lead to various neurological symptoms like hallucinations, excessive sweating, coma, convulsions, a spastic colon and depression.
- Gastrointestinal irritants – cause vomiting, nausea, abdominal cramps and diarrhea.
- Disulfiram-like toxins that only exhibit symptoms if and only if alcohol is consumed (within three days after consumption); the victim will usually experience a short-lived acute toxic syndrome.
Where does the mushroom grow? Is it growing on trees or grassland? What kind of tree are they growing atop or under? Are they growing in a ring or singly, tuft or troop?
Edible mushrooms typically grow in lawns or open paddocks and not under shrubs or trees like the toadstool varieties. Amanitas, for example, start appearing in fall and summer, especially on the floor of woodlands. They are quite common in most places.
The following is a detailed list of some of the common physical characteristics that distinguish edible mushrooms from poisonous ones:
Warts or scales on the cap.
These are universal veil’s remnants that encompass the mushroom while it is young. Sometimes these patches look more like rows of raised dots.
Edible mushrooms have smooth and more or less white caps with no visible or noticeable raised warts or scales. On the contrary, poisonous mushrooms, for instance, the toxic fly agaric have a different colored cap (usually red with white spots) which has conspicuous scales and raised lumps.
Most of the edible mushrooms have bun-shaped or convex caps and sometimes with a wide low-hump. Other edible mushrooms such as chanterelles have caps that are concave and wavy or even trumpet-shaped. Poisonous species, however, have convex caps while young and flattens as the mushroom matures.
The cap of many edible mushrooms stretches from the stem as it grows developing a ring of tissue around the stem also known as the annulus. Toadstools or poisonous varieties do not have this ring around the stem.
Some mushrooms have a rounded cup commonly referred to as the “volva”, which is a universal veil remnant. To observe the swollen base clearly you may have to dig up the mushroom as it’s usually under the ground.
The base of the stem of edible mushrooms is narrow or not thick like the rest of the stalk. On the other hand, many poisonous mushrooms usually have a noticeably swollen base. The Amanita muscaria, for instance, has a bulbous base.
A spore print is an important diagnostic trait for identifying mushrooms. Identifying the color of the spore print can be very helpful as it helps you distinguish the different mushroom varieties. The color of mushroom spore can range from white to black and many other shades depending on the mushroom species. Some of the common poisonous mushrooms such as Amanita have white-colored spore prints.
You can easily obtain a spore print for color-testing by removing the stem and putting the mushroom gills on a dark or white piece of paper for several hours. Once you know the color of the spore refer to a mushroom guide to know the exact species and its edibility.
Another distinctive feature is the size and color of the mushroom’s gills. You will find most of the edible mushrooms with gills attached to the cap and not to the stalk. This means that the gills will stay attached to the cap even when the stalk is removed from the mushroom’s base. The poisonous mushroom’s gills, however, are attached to the stalk and will remain there even after you’ve removed it from the base.
The gills on the cap of a young edible mushroom cap are usually pink in colour. However, the pink colour changes as the mushroom mature to brown or black. On the contrary, poisonous mushrooms have white gills that do not change colour throughout their entire lifecycle.
Another common difference between poisonous and edible mushrooms is their smell. Some mushrooms have distinct smells or a unique smell which can help you to distinguish species that are visually similar. Some of the edible mushrooms, for instance, the Chanterelles have a distinctive fruity smell like apricots. Some of the poisonous species such as Agaricus xanthodermus, commonly known as the yellow-staining mushroom are known for their almond scent.
When you are testing for odors, crush a part of the mushroom’s cap for best results. Many mushrooms lack a smell, while others have quite a distinctive odor; thus, make sure you have a local mushroom guidebook to cross-reference.
Also, you need to keep in mind that not all mushrooms with odors give a certain smell of something as most of them have vague descriptions like “farinaceous,” meaning consisting of or containing starch.