Armillaria mellea

What You Should Know

Armillaria mellea is a basidiomycete fungus in the genus Armillaria. Its cap color has a variety from yellow to red-brown, with a darker area near the center. The cap flesh is white and firm. It is a widely distributed fungus. Grows typically on hardwoods and other living and dead wood in large groups.

It is an edible mushroom when cooked and reported poisonous when raw; high caution is advised due to the similar appearance of other poisonous mushrooms. Fresh mushrooms of the Armillaria mellea contain 95% water, proteins, sugars, minerals calcium, potassium, phosphorus, as well as butyric and propionic acid. There is no scientific evidence to suggest that Armillaria mellea has any psychedelic effects.

This species is capable of producing light at night via bioluminescence in its mycelium. It is one of the most common causes of death in trees and shrubs in both natural and human-cultivated habitats and causes steady and substantial losses.

Other names: Honey Mushroom, Shoestring Root Rot, Boot-lace Fungus, Oak Root Rot Fungus, Echte honingzwam (Netherlands), Václavka Obecná (Czech Republic), Honiggelber Hallimasch (German).

Armillaria mellea Mushroom Identification

1. Cap

   1.38 to 5.91 inches (3.5 to 15 cm), convex, often with squarish sides, when young; expanding to broadly convex or nearly flat in age; dry or slightly tacky; golden yellow when young and fresh, but soon fading to yellowish or brownish; bald, or with a few tiny, yellow to brownish scales concentrated near the center and vaguely radially arranged; the margin sometimes becoming finely lined with maturity.

2. Gills

   Attached to the stem or beginning to run down it; close; short-gills frequent; whitish, sometimes discoloring or spotting pinkish to brownish; covered by a pastel yellow to whitish partial veil before the cap expands.

3. Stem

   2.76 to 7.87 inches (7 to 20 cm) long; 0.20 to 0.79 inches (0.5 to 2 cm) thick; equal above, but tapering to base due to the clustered growth pattern; fairly tough; often bald at maturity, but with whitish to pastel yellow flocculence from the veil when young; whitish to faintly pinkish near apex; becoming grayish to brownish below; with a thin but fairly persistent, white ring that usually features a pastel yellow edge.

4. Flesh

   Whitish to yellowish; unchanging when sliced.

5. Spores

   Ellipsoidal, smooth, with an apiculus; 7-9 x 5-6μm; hyaline, with drops; inamyloid.

6. Spore Print

   Whitish.

7. Habitat

   Grows in deciduous, coniferous, and mixed forests. On forest clearings, gardens, parks, near stumps, tree roots, rotten wood, near the trunks of live trees, in the grass, in groups and very large groups.

8. Season

   July to November.

Armillaria mellea Look-Alikes

1. Armillaria gallica

   There is a bulb and a short stem. The ring turns yellow at maturity.

2. Armillaria tabescens

   Very similar, but without the stem ring, and the gills turn pinkish-brown when mature.

3. Pholiota squarrosa

   Usually similar in color and covered in scales. It retains its curled edges. The gills turn rust-brown and it has a radish-like smell and taste.

4. Armillaria ostoyae

   It has distinctive dark scales on the underside of its persistent stem ring.

Armillaria mellea Life Cycle

This mushroom is found in the soil sporadically throughout the Midwest. The fungus spreads primarily by root-to-root contact or by root-like fungal strands. Root-like fungal strands grow through the soil and adhere to the host roots or root collar that it encounters. Successfully attacked trees do not die until infections girdle the base of the tree. On healthy, vigorous trees, Armillaria is not lethal but if present, it may begin to grow when the tree dies of other causes.

Young trees are more likely to be killed by Armillaria. Trees that are 15–20 years old are more tolerant to attack.

The fungus overwinters and as mycelium or rhizomorphs in diseased trees or in decaying roots. The principal method of tree-to-tree spread of the fungus is through rhizomorphs that grow from infected roots through the soil to the adjacent healthy trees or direct root contact.

Conditions allowing abundant development of soil inoculum of Armillaria make hosts more prone to infection, while at constant inoculum density infection is more likely to occur when trees are weakened. Armillaria species can survive for long periods in colonized wood or as rhizomorphs. The opportunistic lifestyle of Armillaria is explained by its ability to persist when there are no food sources, waiting for conditions that allow the weakening of the host.

Armillaria mellea Bioluminescence

By determining the components involved in the bioluminescence process in luminous and nonluminous organs of the honey fungus Armillaria mellea, we have established causes of partial luminescence of this fungus. The complete set of enzymes and substrates required for glowing in the dark is formed only in the mycelium and only under the conditions of free oxygen access. Since the synthesis of luciferin precursor (hispidin) and 3-hydroxyhispidin hydroxylase in the fruiting bodies is blocked, the formation of luciferin-the key component of fungal bioluminescent system-was not observed. That is why the fruiting body of Armillaria mellea is nonluminous despite the presence of luciferase, the enzyme that catalyzes the oxidation of luciferin with a photon emission.

Armillaria mellea Taxonomy and Etymology

The species was originally named Agaricus melleus by Danish-Norwegian botanist Martin Vahl in 1790. It was transferred to the genus Armillaria in 1871 by Paul Kummer.

The specific epithet mellea means "of honey" and is a reference to the appearance of caps of this species.

Armillaria mellea Synonyms and Varieties

• Agaricus melleus Vahl (1790)

• Agaricus sulphureus Weinm.

• Armillariella mellea (Vahl) P.Karst. (1881)

• Clitocybe mellea (Vahl) Ricken 1915

• Lepiota mellea (Vahl) J.E.Lange (1915)

• Omphalia mellea (Vahl) Quél., 1886

• Armillaria cerasi Velen., 1920

• Armillariella montagnei Singer, 1956

• Armillaria mellea var. minor Barla 1887

• Armillaria mellea var. bulbosa Barla 1887

• Armillaria mellea var. camerunensis Henn. 1895

• Armillaria mellea var. exannulata Peck 1893

• Armillaria mellea var. flava Peck 1897

• Armillaria mellea var. glabra Gillet 1874

• Armillaria mellea var. javanica Henn. 1900

• Armillaria mellea var. laricina (Bolton) Barla 1887

• Armillaria mellea var. maxima Barla 1887

• Armillaria mellea var. obscura Gillet 1874

• Armillaria mellea var. sulphurea (Weinm.) Fr. 1879

• Armillaria mellea var. tabescens (Scop.) Rea & Ramsb. 1917

• Armillaria mellea var. versicolor (With.) W.G.Sm. 1908

Recipe: Sauteed Armillaria mellea Caps and Stems

Ingredients

1. Long clusters of Armillaria mellea and their attached stems

2. Kosher salt and pepper

3. Fat for sauteing like lard, grapeseed or canola

4. 1 Tbsp unsalted butter

Instructions

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

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

3. When the mushrooms are golden and caramelized, add the butter, and season with salt and pepper to taste.

4. Remove the mushrooms to paper towels to drain excess oil, then serve immediately.

Recipe: Honey Balsamic Garlic Mushrooms

Ingredients

1. 1 Tablespoon olive oil

2. 16 ounce Armillaria mellea mushrooms sliced

3. salt and pepper

4. 1/4 cup balsamic vinegar

5. 1 Tablespoon honey

6. 4 garlic cloves minced

7. fresh chopped parsley for garnish

Instructions

1. In a medium-sized skillet over medium-high heat add the olive oil. Add the mushrooms and salt and pepper. Sauté for 1-2 minutes until they start to become tender.

2. In a small bowl whisk balsamic vinegar, honey, and minced garlic. Add the sauce to the mushrooms and continue to sauté for about 3-5 minutes until the sauce reduces and mushrooms are tender and coated in the sauce. Garnish with fresh chopped parsley.

Recipe: Honey Mushroom Stir Fry

Ingredients

1. 50g dried udon noodles

2. 400g Armillaria mellea mushrooms sliced

3. ½ red capsicum, sliced

4. 1 cup broccoli, florets

5. 1 cup cauliflower, florets

6. ½ onion, cut into chunks

Sauce

1. 2 cloves garlic, crushed

2. 2 tsp. ginger, crushed

3. 2 tsp. honey

4. 2 tbsp. soy sauce, salt reduced

5. 2 tbsp. fresh lime juice

6. ¼ cup water plus 2 tbsp

Instructions

1. Boil a small pot of water and cook udon noodles for 4 minutes. Drain and set aside.

2. In a wok or non-stick frypan heat sesame oil and stir fry onion and capsicum for a couple of minutes then add mushrooms, cooking a further couple of minutes. Add broccoli and cauliflower with 2 tbsp. water and half the garlic and ginger then place the lid on top for 1 minute. Take off the lid and stir fry whilst drizzling the honey over.

3. Mix remaining garlic, ginger, soy, lime juice plus water in a small dish, set aside.

4. Place cooked noodles into the pan with sauce ingredients and mix until all combined.

5. Serve immediately.

Recipe: Honey Glazed Mushroom Pork Chops

Ingredients

1. 1 tablespoon olive oil

2. 1 tablespoon butter

3. 8 ounces mushrooms sliced

4. 1 garlic clove minced

5. 4 pork chops around 7 oz each, preferably bone in

6. 1/2 cup white wine

7. 1/2 cup honey

8. 1/4 cup Dijon mustard

9. 1/3 cup chicken broth or water

10. Salt and pepper

11. Finely chopped parsley for garnish

Instructions

1. Place butter and oil in a large skillet over medium-high heat. When the butter has melted and the oil is hot, add mushrooms, salt and pepper. Cook for 3 minutes or until golden, then transfer to a bowl.

2. If the skillet is looking dry, add a touch of oil and return to the stove.

3. Season pork on both sides with salt and pepper. Place in the skillet and cook for 3 minutes on each side, or until golden and cooked to your taste. Remove into a plate and cover loosely with foil.

4. Add white wine into skillet – it will sizzle. Cook for 1 minute, scraping the bottom of the skillet, or until you can no longer smell alcohol. Add remaining ingredients and mix (mustard will dissolve better once it comes to heat but use a whisk if necessary).

5. Simmer for 2 minutes or until it reduces and becomes like a thin syrup. Return mushrooms to the sauce. Adjust salt and pepper to taste, if it's too sweet for your taste to add a tiny touch of cider vinegar.

6. Serve pork, topped with the honey glaze and mushrooms, garnished with parsley if using.

Recipe: Honey mushroom pierogies

Sour cream dough

1. 4 Plain flower

2. 0.25 cup Sour cream

3. 0.50 tsp Salt

4. 1 Egg

5. 1 cup Water

Mushroom Filling

1. 23 Chopped Armillaria mellea mushroom caps, discard the stems

2. 1 Medium onion, chopped

3. 2 tbsp Butter

4. Salt and pepper to taste

Instructions

1. Combine all the dough ingredients in a bowl and mix until it is smooth. If it is too dry add water, a tablespoon at a time. If it is too sticky add flour. again 1 tablespoon at a time.

2. When the dough has a smooth texture turn on to a floured work surface and kneed for 3 or 4 minutes until it is elastic. Cover and refrigerate for 30 minutes.

3. Sauté the onions in the butter on medium until they soften. Add the chopped mushrooms and sauté until they brown and caramelize. Add a pinch of salt and pepper to taste.

4. Put a large pan of water on to boil.

5. Roll out the 1/2 the dough on a flowered surface to about 1/4 inch thick.

6. Cut the dough into circles with a pastry cutter or glass. Fill the dough with mushroom mixture, about a tablespoon per a pierogie and use your finger to run a bit of water around half the circle and fold shut then crimp with your fingers.

7. Roll out the other half of the dough and repeat.

8. Put the pierogies is a pan of boiling water and stir once or twice so that they don't stick to the bottom of the pan or each other. Turn the heat down to a simmer.

9. After a few minutes, the pierogies should float to the surface. I normally let them cook for another minute to two then fish them out and drain in a colander.

10. Fry pierogies in (lots of) butter until crisp and browned.

Armillaria mellea Video

Source:

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