Ultimate Guide To Polypore Mushrooms

Polypore mushrooms decompose the wood on which they grow and play a significant role in carbon dioxide production and nutrient cycling in the forest ecosystem. These mushrooms have also been in use for centuries for their health-restoring benefits.

This article will talk about identifying a polypore mushroom, and understanding which ones are edible and which have medicinal benefits. We will also explore the health benefits of some commonly used polypores like:

• Turkey Tail
• Reishi
• Artist’s bracket
• Birch bracket
• Maitake
• Chicken of the woods
• Chaga
• Dryad’s saddle

What is a polypore?

Polypore mushrooms are a large diverse group of mushrooms that have pores or tubes underneath their cap. Poly means many or much and poros means pore in Greek, so the mushroom is literally named after its many pores.

This hard, brittle mushroom falls under the Basidiomycota (club fungi) division, Agaricomycetes class, and incertae sedis subclass in the fungi kingdom. Polyporales are an order of around 1800 mushroom species which include polypores and the closely related corticioid fungi.

Polypore mushrooms are also called Bracket fungi or Shelf fungi because they characteristically produce fruiting bodies that are bracket or shelf-shaped. These fruiting bodies are tough, sturdy, and woody and are called conks. The brackets can range from a single row of a few caps to several rows of mushroom caps.

Unlike most other mushrooms that produce spores in linear rows or gills, polypores produce spores in a tissue perforated with numerous cylindrical pores. These pores range from 0.2 to 2 mm in diameter and are the sites from where the spores are shed.

Currently, Polyporus is a small genus comprising at least 12 orders, as DNA studies have shifted many fungi out of the polypore order. Classification of polypore mushrooms is based on growth form rather than phylogeny. [1]

How do you identify a polypore mushroom?

Polypore mushrooms can be easily distinguished from other mushrooms that bear pores.

These mushrooms are perennial and can be found even in dry and cold weather. They produce basidiocarps beneath the surface of logs on the forest floor, remaining wet throughout the year.

Other common poroid fungi, like the boletes, fruit on the ground. The pore layer of boletes can be easily peeled off from the flesh. The closely related crust-like corticioid fungi are typically non-poroid and are flat without any recognizable topology.

Paying careful attention to the host tree and the mushrooms’ physical features is often sufficient to reasonably identify polypore mushrooms. Some points to consider are:

Host tree

These mushrooms commonly grow on rotted tree stumps and logs, but can also be occasionally found on living trees. Identifying the host (substrate) tree is also helpful, whether the tree is a hardwood (angiosperms/ deciduous) or softwood (conifer).

Morphology

They typically have a hard exterior and an unusual non-mushroom shape like thin effused patches (or crusts). The appearance of the pore may vary, ranging from small to large, deep or shallow, neatly arranged or maze-like, and can be round, honeycomb-like, or otherwise.

Generally larger the size of the pores, the larger the spores. Top color patterns, shapes, bottom spores’ patterns, and color help with the identification process.

Which popular mushrooms are Polypores?

• Ganoderma spp: Ganoderma lucidum (Reishi mushroom), Ganoderma applanatum (Artist’s conk), Hemlock Varnish Shelf
• Fomes fomentarius (Tinder hoof polypore)
• Climacodon septentrionalis (Northern Tooth Fungus)
• Fomitopsis betulina- previously Piptoporus betulinus (Birch Polypore mushroom or razor strop)
• Fomitopsis pinicola (Red-belted Polypore)
• Trametes versicolor (Turkey tail mushroom)
• Phaeolus schweinitzii (Dyer’s Bracket)
• Cinnabar red polypore
• Laetiporus sulphureus (Sulfur shelf or Chicken of the woods)
• Inonotus obliquus
• Coltricia shelf mushroom

Are polypores poisonous?

Most polypores are non-toxic and some are even edible. However, contrary to the popular belief that “there are no known poisonous polypores”, one genus of polypore mushroom Hapalopilus (H. nidulans), is poisonous. [2]

Consuming this cinnamon-colored polypore mushroom results in dysregulation of central nervous system function and dysfunction of the kidney. It can also lead to nausea, vomiting, abdominal pain, loss of appetite, headache, visual disturbances (like double vision, blurred vision), hallucination, generalized body weakness, violet-colored urine, and multidirectional involuntary eye movement. [3]

What are some edible polypores?

Many edible polypores taste like chicken when cooked. Even the texture and color resemble chicken. Some of the most loved edible wild polypores are:

• Albatrellus spp.,
• Bondarzewia berkeleyi,
• Boletopsis grisea,
• Cerioporus squamosus or Polyporus squamosus (Dryad’s saddle or pheasant’s back mushroom),
• Fistulina hepatica (beefsteak mushroom or ox tongue mushroom),
• Grifola frondosa (Maitake or hen of the woods),
• Ganoderma lucidum
• Ischnoderma resinosum (Resinous polypore),
• Laetiporus cincinnatus and Laetiporus sulphureus (Chicken mushroom, crab of the woods, or chicken of the woods)
• Meripilus sumstinei (Giant blackening polypore),
• Polyporus umbellatus, and
• Sparassis spp  (Cauliflower mushroom)

Which medicinal mushrooms are polypores?

Not all edible polypores have medicinal properties. Some medicinal polypores that are currently in use are:

• Turkey tail mushroom
• Reishi mushroom
• Artist’s conk or Artist’s bracket
• Birch bracket polypore
• Maitake mushroom
• Chicken of the woods
• Chaga mushroom
• Dryad’s saddle
• Resinous polypore
• Tinder hoof

What do polypores do?

Polypore mushrooms are one of the most efficient decomposers of two principal wood components: cellulose and lignin. Through the decomposition of tree trunks, polypore mushrooms recycle a major part of the nutrients in the forest.

Apart from environmental benefits, polypore mushrooms have excellent health benefits. Let’s take a look at the benefits of some of the polypores.

Turkey tail mushroom

Trametes versicolor mushrooms are medicinal polypores that boost the immune system, which is attributable to polysaccharopeptides (PSK and PSP). [4,5]

It has also shown potent anti-inflammatory activity, inhibiting markers of inflammation like NO, IL-6, and TNF alpha. [6]

Turkey tail mushroom is also packed with antioxidants, notably flavonoids and phenols. This helps protect against DNA damage, abnormal mutations, and premature aging. [7]

The PSK in T. versicolor also has anti-tumor potential. Apart from preventing the development of cancer, it also averts its spread. [8]

Other health benefits of Turkey tail include lowering blood sugar and lipid levels. [9,10]

Check out our guide for buying high quality Turkey tail supplements.

Reishi mushroom

Extracts of Ganoderma lucidum are known to have antiviral properties. A Highly oxygenated triterpene (ganoderic acid alpha) isolated from the mushroom has been found to inhibit the activity of the Human Immunodeficiency Virus (HIV). [11,12]

Reishi mushroom also protects against stomach and liver injuries. [13,14] This powerful mushroom also exhibits anti-allergy and anti-inflammatory properties. [15]

Like Turkey tail mushroom, G. lucidum also combats oxidant injury, lowers blood sugar levels, and boosts the immune system [16, 17, 18]

Check out our guide for choosing high quality Reishi supplements.

Artist’s bracket

Lectin, a polysaccharide isolated from Artist’s bracket, has significant anti-cancer activity. The mushroom polysaccharide is toxic to colon cancer cells. [19]

In a 2012 study, researchers have found that G. applanatum has the highest free-radical scavenging activity among several mushrooms. [20] The mushroom has also been shown to benefit heart health. The mushroom supports the synthesis of NO, a potent vasodilator that increases the blood flow to the heart.

Birch bracket polypore

Birch bracket, a polypore that grows on birch trees, has long been used for its medicinal and health-supporting benefits. This mushroom soothes the digestive tract, promotes regular bowel movements, and can ease the discomfort of the stomach. [21]

Extracts of F. betulina also have antiseptic, anti-cancer, and immune-enhancing properties. The mushroom increases the levels of IFN gamma, a cytokine that helps the immune system to respond to intruders in the body. [22]

Maitake mushroom

Extracts of G frondosa exert a protective effect against many disease-causing viruses like Herpes Simplex Virus (HSV-1). The mushroom has also been found to boost the potency of influenza vaccines and suppress the symptoms of the common cold. [23]

Maitake mushrooms can also modulate the immune system. The beta-glucans in the mushroom can activate immune reactions and stimulate the defense system in the body. [24] These beta-glucans are also known to inhibit mediators of inflammation like interleukin and tumor necrotic factors.

As with other medicinal polypores, Maitake has demonstrated anti-tumor activity. Glycoproteins, polysaccharides, D fraction, and MD fraction isolated from Maitake halt the proliferation of tumor cells and induce its apoptosis.  [25] The D fraction of G. frondosa has even been approved by the FDA for use in clinical studies against tumors of the brain, breast, kidney bladder, liver, and prostate.

Maitake mushroom also keeps your blood glucose and cholesterol under control. [26,27]

Chicken of the woods

Sulfur shelf mushroom extracts can suppress the growth of many microorganisms that cause human diseases. The bioactive compound extracted from the mushroom can remove dental plaques and is even used in commercially available dry mouth treatments.

Medicinal chicken of the woods mushroom can decrease the activity of Crohn’s disease. [28] The main bioactive component of L. sulphureus, Eburicoic acid, protects against gastric ulcers and has anti-inflammatory and anti-tumor activity. [29]

Chaga mushroom

I. obliquus is a revered medicinal mushroom as it has documented anti-inflammatory properties. The mushroom releases cytokines, the molecules that control inflammation. [30]

Chaga mushroom also contains beta-glucans, which potentiates the immune system. They enhance the activity of NK cells and helper T cells that play an important role in the identification of destruction of foreign substances. The mushroom can also improve the function of an underperforming immune system. [31]

Triterpenes in Chaga decrease mutation in the cells, thereby protecting them from transforming into cancerous cells. [32] The fungi can also be used as a beauty supplement, helping maintain youthful skin.  

Check out our guide for buying high quality Chaga supplements.

Dryad’s saddle

C. squamosus are high in antioxidants, therefore helping the body fight against free radical damage, trivial cough and cold, and the dreaded cancer cells. Dryad’s saddle also promotes a healthy digestive system.

The lectins in Dryad’s saddle inhibit protein synthesis and induce cellular death. They have also demonstrated significant antimicrobial activity by preventing the adhesion of bacteria and viruses. [33] A 2018 study from Romania has demonstrated both antioxidant and antimicrobial activity. The bioactive compounds in the mushroom have the potential to be utilized as a pharmaceutical and dietary supplement.

How do polypores reproduce?

Polypore mushrooms generally show the normal sexual process shown by club fungi. Germination of two different mating types of haploid spores is required, which find each other to form a mycelium. This dikaryotic mycelium grows by feeding on the host tree. Eventually, a fruiting body is produced and cells thereafter undergo fusion (karyogamy).  This results in a diploid cell that undergoes cell division (meiosis). The resultant basidiospores get dispersed via wind to other trees.

What is the difference between white-rot polypore and brown rot polypore?

Polypore fungi feed on wood, which means it damages the healthy trees and breaks down dead trees. The filiform fungal hyphae of polypore penetrate tree trunks and feed on wood biomass. They cause the decay of birch trees and other hardwood trees.

Wood consists of cellulose, hemicellulose (the white substance), and lignin (the brown substance). Cellulose is the primary wall of the fungus and lignin is the additional second wall inside the cellulose.

There are fundamentally two ways wood can be rotted; decaying the white or brown substance. Accordingly, wood-decaying fungi can be divided into white rot and brown rot fungi.

White rot fungi

A white-rot fungus uses particular enzymes to degrade the lignin, leaving the white cellulose behind. The decomposed wood often changes texture, becoming soft, fibrous, moist, stringy, or spongy. White-rot fungi like Shiitake, are grown all across the globe as a food source.

Some important genera of white-rot polypores are Bjerkandera, Bondarzewia, Ceriporiopsis, Daedaleopsis, Ganoderma, Grifola, Inonotus, Oxyporus, Phellinus, Pycnoporus, Rigidoporus, Trametes, Trichaptum, and Tyromyces.

Brown rot fungi

Brown rot fungi decay only the white cellulose, leaving behind the brown lignin. The decomposed wood cracks into cuboidal pieces, a phenomenon termed cuboidal cracking or fracture.

Some important genera of brown rot polypores are Bridgeoporus, Ceriporia, Daedalea, Laetiporus, Oligoporus, andPycnoporellus.

On occasion, simultaneous white rotters degrade both the lignin and cellulose, albeit at a different rate.

Conclusion

Polypores are a large group of mushrooms that have pores on the underside of their fruiting bodies. Beneficial to the environment and humans alike, these mushrooms are packed with bioactive compounds. 

While not all medicinal mushrooms are polypores, Chicken of the woods, Reishi, and Maitake are some popular medicinal fungal polypores that are edible. These mushrooms have been associated with anti-tumor,anti-oxidant, anti-inflammatory, and immune-boosting properties among many other health-supporting benefits.

References

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