The Complete Guide to Wood Ear Mushrooms

Imagine walking through a forest and seeing a human ear attached to a tree. Well, that’s probably the most common way wood ear mushrooms introduce themselves to novice fungi lovers. But their unique ear-like shape isn’t the only thing interesting about them.

Wood ear mushrooms have been used for centuries as a medicinal tool, and modern research is confirming these benefits (and discovering new ones). What’s more, the folklore behind these fantastic fungi will amaze even the most experienced mycologist. Here’s what you need to know.

What are wood ear mushrooms?

The wood ear mushroom, scientifically known as Auricularia auricula-judae, is a European edible and medicinal species. Known for its unique shape, this fungus has quite a bit of background when it comes to folklore and traditional use. A. auricula-judae also goes by other names, including:

• Jelly ear
• Judas’ ear
• Ear fungus
• Common ear fungus
• Tree ear fungus
• Black fungus
• Kikurage (in Japan)
• Hei mu er (in China)

The genus Auricularia (a classification that groups similar species) brings together different jelly fungus species. If you like mushrooms such as tremella mushroom, you may know by now that jelly fungi are among the most fun and unique species out there (1).

Growing on the wood of deciduous trees, A. auricula-judae shows a unique shape that strongly resembles a human ear. Its brown color doesn’t help it much either—who knows how many beginner mycologists have felt their heart come out of their chest after seeing what looks like a human ear attached to a tree?

Of course, such a suggestive look has led to dozens of folklore stories on the meaning and origin of A. auricula-judae. We’ll go into more detail a bit later—but we’re sure you’ll love this one.

While our ear-shaped shrooms are completely edible, they aren’t considered to be desirable fungi. Their rubbery texture and mild flavor make them a rather unappealing choice for many people. However, A. auricula-judae is common in certain countries’ cuisine, such as Poland.

Pssst: If you’re having a hard time finding these mushrooms in North America, try visiting your local Asian market. You’ll also come across other interesting Auricularia species, such as cloud ear and black wood ear mushrooms.

How do wood ear mushrooms look?

The wood ear mushroom has a cup-shaped, wavy, and irregular 2–15 cm (0.8–6 in) cap that strongly resembles a human ear. Its color ranges from tan to brown, with a silky surface that shows thin veins and a smooth, almost rubbery surface.

The fruiting bodies don’t have a stem; instead, they’re directly attached to the host tree at a central or lateral position. It’s important to know that the fungi’s flesh is considerably thin—handling it without care can break the mushroom. The spore print is completely white (2).

What are the varieties of wood ear mushrooms?

As is often the case with popular mushrooms, the taxonomy of wood ear fungi is notably hard to decipher. This includes varieties, strains, and subspecies—all of which have undergone considerable changes over the years.

Many of the varieties are now considered synonyms for the type A. auricula-judae, previously known as Auricularia auricula-judae var. auricula-judae. However, some of them are still recognized by amateur and professional mycologists.

The first one is Auricularia auricula-judae var. lactea—a rare variety that shows a pale white tone instead of the usual brown. While it’s officially considered a synonym for the type species, it’s still common to find it labeled as “var. lactea” in online forums and shops.

The second one, Auricularia auricula-judae var. delicata, is also sometimes referred to as its own species: Auricularia delicata. We couldn’t find exactly what sets this variety apart from the type species, other than that it seems to be more common in the southern hemisphere.

The same also applies to Auricularia auricula-judae var. polytricha, which is now considered to be simply Auricularia polytricha.

Other, more obscure varieties are now considered obsolete synonyms for the type A. auricula-judae. These include (3):

• Auricularia auricula-judae var. mauritiensis
• Auricularia auricula-judae var. nidiformis
• Auricularia auricula-judae var. tremellosa

Still, it’s rare to find A. auricula-judae labeled so specifically. Moreover, no evidence suggests that these varieties or related species are inedible—so don’t be afraid to experiment.

History of wood ear mushrooms

The odd shape of A. auricula-judae has a rather curious folklore behind it. 

Legend has it that this species first grew on the tree where Judas Iscariot hanged himself. In the Bible, Judas was one of the 12 apostles, famous for having betrayed Jesus Christ for 30 silver coins. It’s said that, after revealing Jesus’ identity to the Sanhedrin, Judas couldn’t handle the guilt of betraying his leader.

He then hanged himself off an elder tree—which is where these curious fungi tend to grow. According to folklore, the ears represent the spirit of Judas cursing the tree on which he decided to end his life.

Mentions of Judas’s ears date back to at least the end of the 16th century. However, some later translators made a crucial mistake: they misunderstood the Latin “judae” for “jew.” This led to the common name “Jew’s ear” being used quite often during those times (4).

But the first scientific description doesn’t appear until 1753, when renowned botanist Carl Linnaeus included it in his pivotal work “Species Plantarum.” He originally placed it under the Tremella genus, giving it the name Tremella auricula.

Famous mycologists Elias Fries and Pierre Bulliard later redescribed the species, transferring it to the Exidia genus and adding the “-judae” to the name. Yet, the currently accepted description dates back to much later: in 1888, Joseph Schröter finally defined it as Auricularia auricula-judae (3).

Health benefits of wood ear mushrooms

Auricularia auricula-judae’s incredible health benefits make it a very popular choice among lovers of “functional mushrooms,” which are fungi with remarkable nutritional and medicinal values.

Experts estimate that a 100-gram serving of dried wood ear mushrooms contains about 65% carbohydrates, 10% protein, and 25% fats, ash, and other compounds (5).

As for its medicinal benefits, A. auricula-judae shows a potent antioxidant activity. This makes it a promising prospect for treating conditions or damage related to aging, inflammation, and tumors.

Another key property is its hypocholesterolemic activity—meaning the species can lower blood cholesterol levels. While the mechanism behind this isn’t fully understood, researchers theorize that wood ear mushrooms could promote certain beneficial bacteria growth in the gut.

Similarly, A. auricula-judae extracts could have significant hypoglycemic and anti-diabetic activities. These extracts contain compounds like polysaccharides and peptides that could reduce glucose blood levels without affecting glucose tolerance.

Like most functional mushrooms, wood ear fungi may also have significant antitumor properties. Experts theorize that these activities act in various ways, such as suppressing the expression of certain tumor-related genes.

Other benefits of Auricularia auricula-judae include radioprotective, anti-inflammatory, immunomodulating, antimicrobial, and anti-fatiguing properties, among others (6).

Although wood ear mushrooms are one of the most promising fungi in modern medical research, it’s important to remember that trials are still in their early stages. If you want to use A. auricula-judae for its medicinal benefits, check with a doctor first.

Where do wood ear mushrooms grow?

Wood ear mushrooms are widespread in Europe, although they may also appear on other continents. Usually, they grow on the wood of deciduous trees and shrubs, such as beeches and spindles, with their favorite being elders (Sambucus nigra). 

A. auricula-judae can grow as a parasite or as a saprotroph—meaning you can find it on dead and live trees. Specimens can grow alone or in a group. Experts point out it’s a year-round mushroom, with a particular emphasis on autumn (2).

What is ethical wildcrafting?

Ethical wildcrafting refers to a series of guidelines that aim to protect your local ecosystem while harvesting. Many people confuse wildcrafting with foraging, but the key difference is that the former refers to harvesting for medicinal purposes and the latter for eating.

Harvesting carelessly can damage animal, mushroom, and tree populations near the patch. But practicing ethical wildcrafting is surprisingly easy if you’re willing to remember these simple rules:

• Do some research before heading out. Make sure to take note of both endangered and poisonous lookalikes you may encounter.
• Carry a field guide. These small books can make a world of difference when you’re out on the field!
• Be mindful of overharvesting. Take only what you need, and don’t share patch locations with others.
• Pick the mushrooms gently. It’s best to use your hands—only use scissors and knives when necessary.
• Check local laws around harvesting on parks and nature reserves. If you’re on private land, ask the owner for permission first.

If it’s your first time on the field, don’t be afraid to seek out local harvesting groups. Most experienced mycologists and mushroom lovers will gladly show you the ropes when it comes to harvesting.

Is it safe to wildcraft for Auricularia auricula-judae?

Unfortunately, it’s never 100% safe to eat wild mushrooms—no matter the species. Even veteran mushroom pickers are at risk of harvesting a toxic or non-edible lookalike. While we aren’t aware of any poisonous lookalikes for wood ear mushrooms, it’s always better to be safe than sorry.

Even if you’re sure you’ve picked the right species, wild fungi often carry toxins and pathogens from the environment. As such, make sure to wash and cook them thoroughly if you are set on eating wild-picked wood ear fungus.

How do you take wood ear mushrooms?

A. auricula-judae isn’t always the most popular choice for cooking mushrooms. It doesn’t have a crunchy texture or strong flavor, but that’s not to say they can’t be incorporated into your dishes.

For example, wood ear mushrooms are relatively common in Asian cuisines as an ingredient in dumplings. They’re particularly common in Chinese cuisine, where they’re a key ingredient in a traditional dish: hot and sour soup.

Hot and sour soup is made by simmering Chinkiang vinegar, white pepper, and water mixed with cornstarch and adding several other ingredients. These range from soy sauce to cilantro, but the most important are mushrooms.

Chinese cooks may add any number of fungi to hot and sour soups, such as morel mushrooms and shiitake mushrooms. But they almost always add dried wood ear mushrooms, which give the soup a crunchy texture (in contrast to rehydrated or fresh wood ear mushrooms).

Another option is an easy yet delicious wood ear mushroom salad. Simply wash, chop, and cook the mushrooms in a little sesame oil, toss them in a bowl, and add any other ingredient you can imagine. Oyster mushrooms are always a great choice, but you can also use vegetables and sauces to spice things up. Keep in mind that you may need some crunchy elements to contrast with the chewy texture of fresh wood ears.

While it can be hard to find wood ear mushroom recipes online, remember that you can always add them to other mushroom-friendly dishes. Stir-fries, soups, and stews are perfect examples of dishes that can incorporate fungi such as wood ears.

Wood ear mushrooms: Simply ear-resistible

Wood ear mushrooms are among the most popular functional fungi that we know of. They have dozens of potential health benefits, from lowering cholesterol blood levels to reducing fatigue. This edible fungus can also fit into several recipes.

If you want to find out about other types of mushrooms, keep up on shroomer. Here, discover everything you need to know about psychedelic and functional fungi from around the world, plus the latest news on medicinal research on edible mushrooms.

References

1. Thomas Volk. “Tom Volk’s Fungus of the Month for April 2004.” TomVolkFungi.net (2004). Recovered from: https://botit.botany.wisc.edu/toms_fungi/apr2004.html
2. Michael Kuo, Andrew Methven. “Auricularia auricula” in Mushrooms of the Midwest (2014), 105.
3. Mycobank. “Auricularia auricula-judae.” (No date). https://www.mycobank.org/page/Name%20details%20page/12901
4. Patrick Harding. “A Word in your Ear” in Collins Mushroom Miscellany (2008), 133–137.
5. FoodData Central. “Fungi, Cloud ears, dried.” April 2018. https://fdc.nal.usda.gov/fdc-app.html#/food-details/168581/nutrients
6. SolJu Pak, Fang Chen, Lingjun Ma, Xiaosong Hu, Junfu Ji. “Functional perspective of black fungi (Auricularia auricula): Major bioactive components, health benefits and potential mechanisms.” Trends in Food Science & Technology 114 (2021): 245–261. https://doi.org/10.1016/j.tifs.2021.05.013