Wild Mushroom Knowledge Classroom | How to Identify Poisonous Wild Mushrooms

How to Identify Toxic Wild Mushrooms

General Characteristics of Toxic Mushrooms

Toxic mushrooms often have bright colors and may have features such as bumps, red spots, grooves, or cracks on the cap. They may also have a volva (base), and a ring on the stalk. When broken, toxic mushrooms typically exude a milky juice with a pungent odor.

Methods to Identify Toxic Mushrooms

1. Growing Area

Edible, non-toxic mushrooms usually grow in clean grasslands or on pine and oak trees. Toxic mushrooms often grow in dark, damp, and dirty areas. However, even edible wild mushrooms can cause poisoning if they grow in fields sprayed with pesticides, fertilized lands, or areas with eucalyptus trees.

2. Color

Toxic mushrooms often have bright and striking colors such as red, green, black, or purple. Particularly, purple mushrooms tend to be highly toxic. Toxic mushrooms generally change color quickly after being picked.

3. Shape

Non-toxic mushrooms usually have a flat cap, smooth surface, and no rings or volva on the stalk. In contrast, toxic mushrooms often have a convex cap with a peculiar shape, a thick and hard surface, and typically feature a ring on the stalk. Their volva may be thin or thick and are easily broken.

4. Secretions

When you break the stalk of a fresh wild mushroom, non-toxic mushrooms will secrete a clear, water-like liquid (sometimes white). The mushroom surface does not change color after being broken. Toxic mushrooms will secrete a thick, often reddish-brown liquid and the surface will change color upon exposure to air.

5. Smell

Non-toxic mushrooms have a distinctive pleasant smell with no off-putting odors. Toxic mushrooms emit strange smells such as spicy, sour, or foul fishy odors.

6. Chemical Identification

Take a sample of the mushroom juice from a suspected mushroom and wet a piece of paper with it. Add a drop of dilute hydrochloric acid or white vinegar to the paper. If the paper turns red or blue, the mushroom is toxic.

By using these methods, you can more safely identify toxic wild mushrooms and avoid poisoning.

Common Edible Wild Mushrooms

Introduction to Mushrooms

Mushrooms, scientifically known as fungi, are a type of organism distinct from plants and animals. Yunnan Province in China is renowned for its rich variety of wild edible mushrooms, boasting over 250 species. This accounts for more than half of the world’s edible mushroom species and two-thirds of those found in China. However, among these, there are over ten species that can cause poisoning if consumed.

Identifying Edible Wild Mushrooms

While indulging in the delicious flavors of wild mushrooms, it is essential to know how to differentiate between edible and toxic varieties. Here are some common edible wild mushrooms:

1. Chanterelle (Cantharellus cibarius)

• Description: Known for its vibrant yellow color, this mushroom has a funnel-shaped cap and a fruity aroma.
• Habitat: Typically found in deciduous forests, often near oak trees.

2. Porcini (Boletus edulis)

• Description: This mushroom has a large, brown cap and a thick, white stalk. It is highly prized for its nutty flavor.
• Habitat: Found in coniferous and deciduous forests, often under spruce and pine trees.

3. Matsutake (Tricholoma matsutake)

• Description: Featuring a distinctive spicy aroma, matsutake mushrooms have a brownish cap with a white stalk.
• Habitat: Grows in the forests of pine, oak, and fir trees.

4. Morel (Morchella esculenta)

• Description: Recognizable by its honeycomb-like appearance, this mushroom has a spongy texture.
• Habitat: Found in moist areas of forests, especially under elm, ash, and apple trees.

5. Shiitake (Lentinula edodes)

• Description: Known for its umbrella-shaped cap, dark brown in color, and savory taste.
• Habitat: Commonly found on decaying hardwood logs, especially oak.

6. Lion’s Mane (Hericium erinaceus)

• Description: This mushroom has a unique appearance with long, white spines resembling a lion’s mane.
• Habitat: Grows on hardwood trees, particularly oak and beech.

Precautions and Poisonous Mushrooms

Recognizing Toxic Mushrooms

While edible mushrooms can be a delightful addition to meals, it is crucial to recognize and avoid toxic varieties. Here are some general guidelines for identifying potentially poisonous mushrooms:

1. Color: Toxic mushrooms often have bright, vibrant colors such as red, green, black, or purple.
2. Cap Surface: The cap may have bumps, red spots, grooves, or cracks. Some may have a volva (cup-like structure) or an annulus (ring).
3. Secretion: When broken, toxic mushrooms often secrete a milky or colored juice with a pungent odor.
4. Habitat: Toxic mushrooms are frequently found in dark, damp, and dirty areas, but even edible mushrooms can be harmful if grown in polluted environments.
5. Chemical Reaction: Extract the juice from a suspicious mushroom and apply it to a piece of paper. Add a drop of diluted hydrochloric acid or vinegar. If the paper changes color (red or blue), the mushroom is likely toxic.

Conclusion

To safely enjoy wild mushrooms, it is best to purchase them from reputable sources such as supermarkets or farmers’ markets, where cultivated varieties are sold. Avoid picking wild mushrooms unless you are an expert in identifying safe species. If symptoms of mushroom poisoning occur, such as dizziness, nausea, vomiting, abdominal pain, or hallucinations, seek medical attention immediately and follow the recommended self-rescue measures.

Beware of Mushroom Poisoning in Summer

As summer arrives, with higher temperatures and increased rainfall, wild mushrooms thrive. This season also sees a rise in mushroom poisoning incidents. During picnics and outings in rural areas, people often come across various wild mushrooms with different colors and shapes. Some may pick these mushrooms and take them home to eat. However, if symptoms like dizziness, nausea, vomiting, abdominal pain, diarrhea, restlessness, or hallucinations occur after consumption, it could be mushroom poisoning, which in severe cases can be fatal. Many edible and toxic mushrooms look extremely similar, making it difficult even for mycologists to distinguish them by sight. Therefore, the most effective way to avoid mushroom poisoning is not to pick, buy, or eat wild mushrooms.

Seven Common Misconceptions About Toxic Mushrooms

Misconception 1

Brightly colored mushrooms are poisonous, while ordinary-colored mushrooms are safe. Color and shape alone cannot distinguish whether a mushroom is poisonous. For instance, the brightly colored chanterelles, suillus, and russula are delicious and edible, whereas the deadly amanita mushrooms, which are extremely toxic, are gray or white.

Misconception 2

Mushrooms growing in damp places or on animal dung are poisonous; mushrooms growing under pine trees or in clean areas are safe. Most mushrooms grow in dark, damp places, but not all are edible. Some poisonous mushrooms do indeed prefer growing on dung, like certain toxic species of coprinus and stropharia. However, some toxic mushrooms like certain species of amanita, champignon, and russula also grow in pine forests.

Misconception 3

Cooking mushrooms with silverware, ginger, rice, or scallions, and if the liquid turns black, they are poisonous; if not, they are safe. Mushroom toxins do not react with silverware. The most toxic amanita toxins do not cause any color reaction.

Misconception 4

Mushrooms with secretions or those that change color when injured are poisonous. Some juicy mushrooms change color when injured and are not only non-toxic but also tasty and edible.

Misconception 5

Mushrooms infested with maggots or insects are non-toxic. Many highly toxic amanitas also develop maggots and insects when they mature.

Misconception 6

Toxic mushrooms turn water cloudy when soaked; non-toxic mushrooms keep the water clear. Water turning cloudy is due to the presence of sap, which can be found in both toxic and non-toxic mushrooms. Many toxic mushrooms do not turn the water cloudy when soaked.

Misconception 7

Cooking destroys the toxins in poisonous mushrooms. The toxins in poisonous mushrooms are stable and heat-resistant, meaning that regular cooking methods cannot destroy them. Adding other ingredients like garlic or ginger also cannot neutralize the toxins.

All Toxic Mushrooms with Photos and Chinese Name

Self-Rescue Measures After Consuming Toxic Mushrooms

If you suspect mushroom poisoning after eating wild mushrooms, immediate self-rescue measures and prompt medical attention are crucial.

Self-Rescue Measures:

1. Drink a large amount of clean water immediately (at least 1000 milliliters).
2. After drinking, use a spoon or chopsticks to stimulate the back of your throat to induce vomiting, repeating this process until only clear water is expelled to minimize toxin absorption in the gastrointestinal tract.
3. Seek immediate medical treatment at a regular hospital or call emergency services at 120.