Armillaria ostoyae

What You Should Know

Armillaria ostoyae, also known as the honey mushroom, is a type of edible mushroom known for its slightly sweet and earthy flavor and chewy texture. It is also a good source of antioxidants, which can help protect against chronic disease by neutralizing free radicals. However, it must be cooked before consumption, as it is unsafe to eat raw and can cause serious side effects. It is commonly found in Europe, parts of Asia, and North America. It grows on both hardwood and conifers, has a ring on its stem, and has cream-brown colored caps with distinct scales.

This fungus causes growth loss and butt rot in trees, leading to high mortality rates in conifers in plantations and natural stands. Losses are higher in conifers than in hardwoods.

Armillaria ostoyae reproduces sexually. It starts as spores released by mature mushrooms and has a white spore print. There are two mating types for spores. Spores can be spread by wind or animals. When two spores of the same species and different mating types fuse, they form colonies that become dark brown and flat. The fungus forms mycelial cords, also called rhizomorphs, which allow it to obtain nutrients over long distances, making it a pathogenic fungus.

It also has many unique and intriguing biological properties, some of which may hold great benefits for mankind. Bioluminescence (glow at night), bioremediation, medicinal properties, and mycorrhizal associations are some of the most interesting attributes of Armillaria ostoyae

Armillaria ostoya can cause serious side effects if consumed raw. Some individuals may not be able to tolerate them even after cooking and may experience nausea, cramps, and stomach pain. If you experience any side effects, discontinue use immediately. Avoid consuming alcohol with these mushrooms and certain species should not be eaten within 12-24 hours of drinking alcohol.

Other names: Honey Mushroom, Dark Honey Fungus, Shoe-String, Czech Republic (Václavka Smrková), Netherlands (Sombere honingzwam), German (Dunkler Hallimasch, Gemeiner Hallimasch).

Armillaria ostoya Mushroom Identification

1. Cap

   0.79–5.91 in (2–15 cm) cm in diameter, initially hemispherical or convex, with a bent edge, with a cotton-like membranous covering the gills, later convex-expanded, almost flat-expanded, with a tubercle in the middle, with a thin, pubescent edge. The surface of the cap is brown, reddish-brown, grayish-brown, and dark brown, covered with darker scales, thicker and darker in the center, with flaky remnants of the general cover on the edges.

2. Gills

   The hymenophore is lamellar. Gills are thick or of medium thickness, thin, accreted, sometimes slightly descending on the stem, initially whitish-yellowish, later darker.

3. Stem

   1.97–4.72 in (5–12 cm) high, 0.16-0.39 in (0.4-1.0 cm) in diameter, thickened to the base, straight or bent, solid, in mature specimens with a cavity, with a rapidly disappearing ring, fibrous. Has the same color as the surface of the cap or lighter, covered with light flaky scales, almost bare with age. The ring is whitish, quickly disappearing.

4. Flesh

   Fleshy, dense, whitish, with a pleasant mushroomy smell. Sometimes becoming pinkish-brown with maturity; often yellow in the stem base; unchanging when sliced.

5. Odor and Taste

   Weak acidic odor. Some people think it tastes somewhat sweet, but they could be reading that in from the name. Other people taste a mildly-bitter aftertaste.

6. Spores

   Oval, broadly elliptical, 8–10 x 5–7 µm, smooth, colorless.

7. Spore Print

   White.

8. Habitat

   Grows in deciduous and mixed forests, clearings, stumps and near them, tree roots, rotten wood and near trunks of living trees in groups and large groups.

9. Season

   September to November.

Armillaria ostoyae Look-Alikes

1. Armillaria gallica

   Grows mainly on hardwoods at lower elevations, and has a conspicuous tuber-like expanded base of the stem.

2. Armillaria borealis

   Produces slimmer and light-colored fruiting bodies with light scales on the cap. It usually grows in rich clumps on hardwoods.

3. Armillaria tabescens

   There are no stem rings, and the gills turn pink when they mature.

4. Armillaria mellea

   The cap is scaly with a yellowish stem ring. The ring does not have dark scales on its underside.

5. Pholiota squarrosa

   Usually similar in color and covered with scales. The gills turn rust-brown. It has a radish-like smell and taste.

6. Armillaria cepistipes

   Grows on conifers and deciduous trees, with fine scales on the cap, and an expanded base of the stem.

Armillaria ostoyae Health Benefits

1. Rich in antioxidants

   Honey mushrooms are a good source of antioxidants, which can protect against chronic disease by neutralizing free radicals. Studies have shown that specific compounds from honey mushrooms can effectively scavenge free radicals and prevent damage to cells.

2. Could help fght cancer cell growth

   While more research is still needed to determine how honey mushrooms may affect cancer in humans, some studies show that it could help block the growth and spread of cancer cells in vitro.

3. Protects brain health

   One of the most promising uses for honey mushroom treatment is its potential to enhance brain function and protect against neurodegenerative disorders.

4. May stabilize blood sugar

   High blood sugar can come with serious consequences, ranging from impaired headaches and increased thirst to impaired wound healing and vision problems.

Read This Before Using Armillaria ostoyae Extract

Armillaria ostoyae extract is a concentrated form of the mushroom that contains beneficial compounds. It is commonly used in dietary supplements and traditional medicine to promote health and wellness. However, it is important to note that the safety and effectiveness of using Armillaria ostoyae extract as a supplement have not been thoroughly studied in humans, so it is recommended to consult with a healthcare professional before adding it to your diet.

Armillaria ostoyae Taxonomy and Etymology

The species Armillaria ostoyae was first described by Henri Charles Louis Romagnesi in 1970, under the name Armillariella ostoyae. It was later moved to its current genus and renamed by Czech mycologist Josef Herink in 1973. Some experts, particularly in the USA, now prefer the name Armillaria solidipes Peck, based on a honey-colored mushroom that they believe is the same as the Dark Honey Fungus and was described by American mycologist Charles Horton Peck in 1900.

The common name "Honey Mushroom" is derived from the color of the caps of Armillaria ostoyae. The specific epithet "ostoyae" may be a reference to Ostoja, also known as Dzerzhanovka, in Ukraine, possibly where the type specimen was collected from.

Armillaria ostoyae Synonyms

• Armillariella ostoyae Jahn, H. & M.-A. Jahn

• Agaricus congregatus Bolton, 1791

• Agaricus obscurus Schaeff. 1774

• Agaricus polymyces Pers. 1797

• Armillaria mellea var. obscura Gillet, 1874

• Armillaria obscura (Schaeff.) Herink 1973

• Armillaria polymyces (Pers.) Singer & Clémençon

• Armillaria solidipes Peck, 1900

• Armillariella obscura (Schaeff.) Romagn. 1978

• Armillariella ostoyae Romagn., 1970

• Armillariella polymyces (Pers.) Singer & Clémençon 1973

• Lepiota polymyces (Pers.) Gray

Armillaria ostoyae Cooking Notes

Honey mushrooms are not only healthy but also delicious, versatile, and easy to use in different recipes. They have a sweet and earthy taste, a chewy texture, and can be added to pasta, soups, and stuffings to enhance the flavor and provide extra antioxidants.

Recipe: Armillaria ostoyae Paprikas

Ingredients:

1. 3 c. packed honey mushroom caps, sliced

2. 2 tablespoons oil

3. 1 medium onion, diced

4. 2 large cloves of garlic, minced

5. 1 tablespoons paprika

6. 1 teaspoon salt

7. 1/4 teaspoon pepper

8. 1-11.5 oz can V8

9. cooked egg noodles or dumplings

Instructions:

1. Blanch the sliced honey mushroom caps in a pot of water for a minute and drain.

2. Sautée the diced onion in the oil until soft, and add the minced garlic. Sautée for 2 minutes longer.

3. Add the paprika and the blanched mushrooms to the onions and garlic and cook over medium heat for 10 minutes.

4. Add the can of V8, and cook for 10 minutes longer, until the liquid has reduced by half. Add the salt and pepper to taste, and serve over hot noodles or dumplings. Robert also likes this on bread.

Recipe: Sauteed Armillaria ostoyae

Remember to always cook honey thoroughly, make darn sure they are done. If they are not cooked through they could give you an upset stomach.

Ingredients:

1. Long clusters of honey mushrooms and their attached stems

2. Kosher salt and pepper

3. Fat for sauteing, like lard, grapeseed or canola

4. 1 teaspoon unsalted butter

Instructions:

1. Trim the caps from the honey mushrooms and peel the stems.

2. Heat a pan with oil until lightly smoking and add the mushroom caps, cook the caps for 3 minutes on high heat until lightly colored, then add the stems and saute for another 3 minutes.

3. Continue cooking the mushrooms until they are well colored and thoroughly cooked.

4. When the mushrooms are golden and caramelized, add the butter, and season with salt and pepper to taste. Remove the mushrooms to paper towels to drain excess oil, serve immediately.

Sources:

Photo 1 - Author: Henk Monster (Creative Commons Attribution 3.0 Unported)

Photo 2 - Author: Kai Löhr (Creative Commons Attribution 4.0 International)

Photo 3 - Author: Michel Langeveld (Creative Commons Attribution-Share Alike 4.0 International)

Photo 4 - Author: Dr. Hans-Günter Wagner (Creative Commons Attribution-Share Alike 2.0 Generic)

Photo 5 - Author: James Lindsey (Creative Commons Attribution-Share Alike 2.5 Generic)