Cloud Ear Fungus (Auricularia polytricha)
Cloud Ear Fungus (Auricularia polytricha)
Cloud Ear Fungus (Auricularia polytricha) is a gelatinous, ear-shaped wood-rotting fungus found on hardwood trees across tropical and subtropical regions worldwide. It has been cultivated in China for at least 1,400 years — longer than nearly any other mushroom — and is one of the most commercially produced edible fungi on Earth, with a 1,300-ton annual harvest in Taiwan alone. It is also one of the most taxonomically misunderstood, with the name covering at least three distinct species depending on who is using it and when.
Auricularia polytricha (Mont.) Sacc. (1885) — Family Auriculariaceae — Order Auriculariales
Cloud Ear Fungus (Auricularia polytricha) is one of the most commercially significant edible mushrooms in the world — yet virtually every aspect of its science is more complicated than its simple appearance suggests. It has been consumed for over a millennium, is produced in millions of tons annually across East Asia, and is the subject of genuine biomedical research. It is also routinely misidentified, carries a name that formal taxonomy has now formally synonymized with an older one, and is sold as up to three different fungi depending on the market. A guide that takes all of this seriously offers something no existing consumer-facing resource does.
Interested in this species? Out-Grow carries a liquid culture.
Cloud Ear Fungus (Auricularia polytricha) Liquid CultureWhat Is Cloud Ear Fungus (Auricularia polytricha)?
Cloud Ear Fungus (Auricularia polytricha) is a jelly fungus in the family Auriculariaceae, producing thin, rubbery, ear-shaped fruiting bodies that grow laterally from hardwood branches and trunks across tropical and subtropical environments worldwide. Its most recognizable feature is the contrast between its two faces: the underside (hymenial surface) is smooth, pinkish to dark brown, and bears the spores; the upper surface is densely covered in coarse, visible hairs that give it a distinctly velvety or fuzzy texture — the defining macroscopic character that separates it from related species.
The fungus is a white-rot saprotroph, meaning it secretes enzymes that break down lignin in dead wood, eventually decomposing the entire wood matrix. Because it does not require a living tree partner, it can be cultivated on sterilized or pasteurized lignocellulosic substrate — sawdust, straw, rice husks, even agricultural waste — without a mycorrhizal host. This biology is the foundation of its extraordinary cultivation history.
The culinary appeal of cloud ear is primarily textural. The fresh fruiting body has an elastic, slightly crunchy consistency that survives cooking without dissolving. The dried form contracts to a fraction of its size and rehydrates fully in 15–20 minutes, swelling back to near-original dimensions — a property that makes it one of the most shelf-stable ingredients in Asian pantries. The flavor is mild and earthy, almost negligible; it is used for texture, visual drama, and the bioactive compounds it contributes to broth and dishes.
The oldest cultivated mushroom: The Chinese agricultural text Tang Ben Cao (~600 AD) describes the deliberate cultivation of Auricularia (as 木耳, Mù'ěr), making cloud ear one of the first mushrooms known to have been farmed by humans. This predates formal records of shiitake cultivation and most other edible fungi by centuries. The species has been consumed in East Asia for at least 1,400 years, appearing in traditional texts as a tonic, cardiovascular aid, and culinary ingredient.
How Is Cloud Ear Fungus (Auricularia polytricha) Classified?
The taxonomy of cloud ear fungus is more complicated than almost any other species in this guide series, and understanding it matters for interpreting the cultivation and chemistry literature correctly.
The name Auricularia polytricha was established in 1885 by Pier Andrea Saccardo, who transferred Exidia polytricha Mont. (originally described from India in 1834) into Auricularia. This name was used globally for well over a century. In 2013, a comprehensive phylogenetic revision of North American Auricularia by Looney, Birkebak, and Matheny demonstrated that the species called A. polytricha in the Americas is actually the same organism as Peziza nigricans Sw. — a name published by Swedish botanist Olof Swartz from a Jamaican collection in 1788, 46 years earlier. Under the principle of nomenclatural priority, the oldest validly published name wins. The combination Auricularia nigricans (Sw.) Birkebak, Looney & Sánchez-García is now the formally accepted name, confirmed by a 2021 global multi-locus phylogenetic study of 277 specimens from 35 countries.
| Rank | Taxon |
|---|---|
| Kingdom | Fungi |
| Phylum | Basidiomycota |
| Class | Agaricomycetes |
| Order | Auriculariales |
| Family | Auriculariaceae |
| Genus | Auricularia Bull. (1786) |
| Trade name | Auricularia polytricha (Mont.) Sacc. (1885) |
| Current accepted name | Auricularia nigricans (Sw.) Birkebak, Looney & Sánchez-García |
Why "A. polytricha" still matters: This guide uses Auricularia polytricha as the primary name because it is what virtually all commercial sources, cultivation literature, bioactivity research, and product labels use. However, there is a second and more practically important complication: the vast majority of cultivation and pharmacology research published under the name "A. polytricha" from China and other Asian countries most likely refers to Auricularia cornea Ehrenb. — a distinct species that was called "A. polytricha" throughout Asia for over 100 years. The 2021 Wu et al. phylogenetic study confirmed this. What this means in practice: when you read a study about "A. polytricha" cultivation yields or polysaccharide bioactivity published in a Chinese journal, there is a strong probability it is describing A. cornea biology. This ambiguity is flagged throughout this guide wherever it affects interpretation of the data.
How Do You Identify Cloud Ear Fungus (Auricularia polytricha)?
Cloud Ear Fungus (Auricularia polytricha) is reasonably distinctive among jelly fungi, though separation from closely related Auricularia species requires attention to the upper surface character that most foragers overlook.
Fruiting bodies are thin, rubbery-gelatinous, ear-shaped to irregularly lobed, typically 2–15 cm across. They attach laterally to substrate without a meaningful stalk. The underside (hymenial face) is smooth to slightly veined, pinkish to dark brown. The upper face is the key character: densely covered in coarse hairs visible to the naked eye, giving a distinctly velvety or furry texture. These hairs measure 650–1,080 µm in length — much longer than the hairs of the related Auricularia auricula-judae (Jelly Ear), whose 100–350 µm hairs give a comparatively smooth appearance. When fresh, the fruiting body is elastic and pliant; when dried, it contracts dramatically to a hard, thin, nearly translucent sheet and swells back fully on rehydration.
Color is variable and substrate-influenced — specimens on lighter-barked wood tend toward amber or yellowish-brown; those in deeper shade or on darker bark trend toward dark brown to nearly black. Age also shifts appearance: young specimens are cup-shaped and concave before expanding to the ear form; old specimens lose their white hymenial bloom and become darker. Color alone is not diagnostic.
Lookalike Species
Auricularia cornea
Nearly identical macroscopically; also has a tomentose (hairy) upper surface. Confirmed distinct by ITS + rpb2 molecular analysis. In most of Asia, what is sold as A. polytricha is almost certainly A. cornea. The two cannot be reliably separated in the field; microscopy or molecular data required.
Auricularia auricula-judae (Jelly Ear)
Similar ear shape and gelatinous texture. Key separator: much shorter, finer hairs (100–350 µm vs 650–1,080 µm) giving a smoother surface. Smaller spores. More common in temperate Europe on elder. Fully edible.
Auricularia heimuer
Smoother upper surface (shorter hairs); distributed in highland China. Confirmed as a distinct species by molecular analysis in 2014. Fully edible.
Exidia spp. (Witches' Butter)
Similar gelatinous texture; more lobed or brain-like shape; lacks the distinct hairs visible under a 10× hand lens. No transversely septate basidia. Not dangerous — some edible — but easily separated by checking for surface hairs.
Tremella spp.
Lobate, brain-like or yellowish-white; no ear shape; different basidial type (longitudinally divided rather than transversely septate). Not dangerous; some species edible.
Microscopic field tip: The most reliable way to separate A. polytricha from A. auricula-judae in mixed temperate zones is hair length: measure hairs under a student microscope. Greater than 500 µm and Q-ratio (spore length/width) greater than 2.4 favors A. polytricha. For separating A. polytricha from A. cornea, ITS + rpb2 sequencing is required — microscopy alone is insufficient.
Where Does Cloud Ear Fungus (Auricularia polytricha) Grow?
The true Auricularia polytricha (= A. nigricans per current taxonomy) is primarily distributed across the Americas — the Caribbean, Central America, southeastern USA, and Mexico — along with parts of Asia. The species marketed and cultivated throughout East and Southeast Asia as "A. polytricha" is most likely A. cornea, concentrated in tropical and subtropical China, Taiwan, Malaysia, the Philippines, India, and Southeast Asia.
In nature, the fungus colonizes dead or weakened branches, fallen trunks, and stumps of a wide range of broadleaf (angiosperm) hardwood species. Documented hosts include elder (Sambucus), maple, beech, elm, mango, acacia, and numerous tropical hardwoods. Growth on gymnosperm (conifer) wood is exceptional and not typical for this species. In temperate North America, wild fruiting has been documented from spring through early winter, with reports of collection as late as mid-January in Wisconsin during mild winters. In tropical regions, year-round fruiting is possible when humidity is adequate.
The species is common in disturbed habitats and not considered at conservation risk. Extensive commercial cultivation across East Asia has also established a large cultivated population. No invasive range issues have been documented.
Can You Cultivate Cloud Ear Fungus (Auricularia polytricha)?
Yes — and this is one of the more beginner-accessible species for indoor cultivation. Cloud Ear Fungus (Auricularia polytricha) is a fully saprotrophic white-rot fungus with no mycorrhizal dependency, a broad substrate tolerance, documented biological efficiencies above 100% on optimized substrates, and a mycelium that grows relatively quickly on agar and colonizes substrate bags in 3–5 weeks. The cultivated species in Asia (most likely A. cornea) has been commercially produced for over a millennium, making it one of the most agronomically mature mushroom species in existence.
Agar Culture Behavior
On MEA (Malt Extract Agar) and PDA (Potato Dextrose Agar) — the two best-performing media — the mycelium grows white to grey-white with a glossy surface that can appear slightly honeycomb-like. It is notably fast, colonizing a 100mm plate in approximately 4–5 days at the optimal temperature of 77°F (25°C). The broad temperature tolerance (59–86°F; pH 3–9) makes it forgiving for hobbyists. Because of its rapid growth, subculture early — transfer wedges from the leading edge at 3–5 days — to avoid overly thick or aging colonies. Maintain stock cultures at 35–43°F in sealed containers, refreshing every 2–3 months.
Full Cultivation Protocol
Agar Expansion
Expand from liquid culture onto PDA or MEA. Incubate at 25°C (77°F). Transfer at 3–5 days from colony leading edge. Colony appears white to grey-white, glossy, with even radial growth. Broad pH tolerance (3–9) means common agar preparations work well.
Grain Spawn
Inoculate sterilized grain (wheat, sorghum, rye) with agar wedges or liquid culture at 2–5% spawn rate. Incubate at 25–30°C, 70–95% RH, in darkness. Colonization rate on grain is approximately 16 mm/day (sweet sorghum data), making spawn run relatively fast.
Substrate Preparation
Hardwood sawdust is the standard base substrate. Proven supplements: rice bran, wheat straw, corn stover, agricultural wastes. Best-performing documented mix: 60% Phragmites stalk + 30% sawdust + 9% rice bran + 1% CaCO₃ — biological efficiency 148.12%. Sterilize at 121°C for 80 minutes minimum, or pasteurize at 60°C for ≥30 minutes for bulk straw substrates.
Spawn Run
Incubate inoculated bags at 25°C, 90–95% RH, in darkness. CO₂ can build to 5,000–20,000 ppm — this is tolerated and expected. Avoid premature light exposure (keep below 500 lux) or primordia may form prematurely. Full colonization typically takes 25–38 days depending on substrate density and temperature.
Fruiting Induction
Trigger fruiting with: a temperature drop to 21–28°C; humidity increase to 85–90%; and increased fresh air exchange (FAE) to drop CO₂ below 500 ppm. Some light exposure aids primordia formation. Primordia appear 5–27 days after conditions are established. Keep humidity consistent — fluctuations cause deformed fruiting bodies.
Harvest
Harvest when fruiting bodies have fully expanded but before edges begin to deteriorate. Expect 4 flushes over approximately 3 months on well-prepared substrate. Allow 7–10 days between flushes. Fresh fruiting bodies can be used immediately or dried for long-term storage.
Biological Efficiency Data
| Substrate | Biological Efficiency | Source |
|---|---|---|
| 60% reed stalk + 30% sawdust + 9% rice bran + 1% CaCO₃ | 148.12% (4 flushes) | Liang et al. 2016 (Taiwan) |
| 30% corn stalk + sawdust + rice bran + CaCO₃ | 145.05% | Liang et al. 2016 |
| 90% sawdust + 9% rice bran + 1% CaCO₃ (control) | 99.49% | Liang et al. 2016 |
| Paddy straw + wheat bran 3:1 | 59.04% | Tamil Nadu Agricultural University |
| Rice straw : sawdust 80:20 | Best substrate in study | Aguilar et al. 2024 (Philippines) |
Biological efficiency values above 100% are achievable because BE is calculated on dry substrate weight against fresh mushroom weight — the high water content of fresh fruiting bodies (over 90%) inflates the percentage. The key takeaway is that substrate supplementation with nitrogen-rich additives (rice bran, wheat straw) substantially improves yields over plain sawdust.
Contamination Risks
The primary fungal contaminants documented on A. polytricha cultivation are Mucor spp., Trichoderma longibrachiatum, and Hypocrea koningii on fruiting body surfaces, and Coprinellus radians on stalks. Trichoderma (green mold) is the most serious competition in the substrate itself, capable of causing up to 70% yield losses in mushroom cultivation generally. Proper sterilization (121°C, 80 min for sawdust bags) is the most effective prevention. Bacterial contamination of post-harvest products is also documented — store harvested fruiting bodies under cold chain conditions and cook thoroughly before consumption.
How to Use a Cloud Ear Fungus Liquid Culture
A Auricularia polytricha liquid culture (LC) syringe contains viable mycelium in sterile nutrient solution, ready to use immediately. The primary documented applications are: grain spawn inoculation (LC → sterilized wheat, sorghum, or rye berries as the spawn production step); agar plate expansion (LC → PDA or MEA for culture maintenance and strain preservation); and substrate bag inoculation for fruiting body production. Liquid culture is also well-suited for mycelial biomass production in submerged fermentation — polysaccharide yields of up to 9.42 g/L have been documented from optimized liquid fermentation of A. polytricha, making LC the practical starting point for anyone interested in the bioactive compound applications of this species.
On agar, expect white to grey-white mycelium with a slightly glossy, honeycomb-like surface texture, colonizing a 100mm plate in 4–5 days at 77°F. Store fully colonized plates at 35–43°F in sealed containers; subculture every 2–3 months to maintain culture vigor.
What Bioactive Compounds Does Cloud Ear Fungus (Auricularia polytricha) Contain?
Cloud Ear Fungus (Auricularia polytricha) has a well-developed bioactivity literature, though the taxonomic ambiguity noted in Section 2 means many studies labeled "A. polytricha" from Asian research institutions are most likely describing Auricularia cornea. The most important non-polysaccharide compound — adenosine — has the strongest evidence base and is the only one with documented pharmacological effects at culinary doses in humans.
Polysaccharides (ABPs / IAPs)
The dominant bioactive class. Fruiting body polysaccharides (ABPs) have MW ~5.40 × 10⁶ Da and 10.38% uronic acid content. Mycelial polysaccharides (IAPs) have lower MW (~1.95 × 10⁶ Da) and lower uronic acid (3.33%). Both resist simulated digestion and maintain antioxidant activity in vitro. In Vitro
Adenosine
154 µg per gram dry weight. Inhibits ADP-induced platelet aggregation via adenosine A₂A receptor activation. This effect has been documented in human subjects at culinary consumption doses — the strongest translational evidence of any compound in this species. Human Case
Immunomodulatory Protein (APP)
13.4 kDa protein; agglutinates mouse red blood cells; activates murine splenocytes; enhances IFN-γ secretion; increases NO and TNF-α production by macrophages. Classified as an immune stimulant. In Vitro
Ergosterol
Pro-vitamin D2; present in fruiting bodies. Isolated ergosterol from A. polytricha attenuated bisphenol A-induced microglial inflammation in a 2022 study. In Vitro
Cerevisterol / 9-Hydroxycerevisterol
Phytosterols identified in A. polytricha. 9-Hydroxycerevisterol was identified as an antinociceptive (pain-reducing) constituent in a 2002 Planta Medica study using an animal pain model. Animal Model
APL Glycoprotein
Novel glycoprotein (1.15% carbohydrate content) reported to adsorb lead, inhibit organ accumulation, and upregulate detoxifying proteins in rats. Described as the first mushroom protein shown to protect against lead-induced hepatotoxicity. Animal Model
Hispidin-Derived Polyphenols
Heat-stable components that inhibit BACE1 (β-secretase) activity in vitro — a target relevant to Alzheimer's disease research. Only inhibitory BACE1 species were detected in A. polytricha, unlike some other edible mushrooms that showed activating effects. In Vitro
Melanin
Produced via tyrosinase-catalyzed pathway in fruiting body development. Tyrosinase is dramatically upregulated during fruiting body formation compared to mycelium — explaining the color shift from white mycelium to dark brown fruiting body. Being explored for cosmetic applications.
The polysaccharides have demonstrated anti-hypercholesterolemic effects in animal models — specifically, a soluble polysaccharide (SPAP) decreased serum total cholesterol by approximately 34% in rats at 4.5 mg/kg body weight. An antitumor polysaccharide (APP) combined with low-dose cyclophosphamide inhibited tumor growth and lung metastasis in tumor-bearing mice via the TLR4/MyD88/NF-κB signaling pathway. These are animal model findings; no human clinical data exists for any of these effects. Animal Model
The volatile chemistry of dried A. polytricha, analyzed in a 1995 Korean GC-MS study, identified 30 compounds. The most abundant by weight were fatty acids — hexadecanoic acid (16.74%), pentadecanoic acid (7.59%), and tetradecanoic acid (3.37%). The characteristic "mushroom" aroma compound 1-octen-3-ol was detected at 1.26%. A 2019 Chinese study on cultivated specimens identified 1-octen-3-ol, hexanal, heptanoic acid, and 1-nonanol as key flavor substances. The mild, almost neutral aroma of this species is consistent with the low levels of potent volatiles detected across both studies.
Is Cloud Ear Fungus (Auricularia polytricha) Safe to Eat?
Cloud Ear Fungus (Auricularia polytricha) has been consumed safely in East Asia for over 1,400 years and is considered one of the safer edible fungi. No amatoxins, hallucinogens, or primary acute toxic syndromes have been documented. However, it is pharmacologically active at culinary doses in one documented and clinically significant way: it inhibits platelet aggregation.
The platelet aggregation effect — documented in humans: Adenosine content of 154 µg per gram dry weight inhibits platelet function via adenosine A₂A receptor activation, analogous in effect (though not mechanism) to aspirin. In 1980, a case published in the New England Journal of Medicine described "Szechwan Purpura" — a researcher who discovered his own platelets would not aggregate after consuming Auricularia polytricha. The effect was reproduced in volunteers. Duration of platelet inhibition after consumption: 3–24 days. Clinical guidance: do not consume in the days prior to surgery or invasive procedures. Use with caution alongside anticoagulant or antiplatelet medications (aspirin, clopidogrel, warfarin). Contraindicated in patients with bleeding disorders.
Beyond the antiplatelet effect, microbial safety of commercial products warrants standard food handling precautions. A Taiwanese study identified Bacillus cereus (a toxin-producing bacterium), Pseudomonas tolaasii, and Cronobacter sakazakii in commercial A. polytricha beverages associated with reported diarrhea cases. These findings underscore the importance of proper storage, cold chain maintenance, and thorough cooking of commercial products.
No IgE-mediated allergy specific to A. polytricha has been documented in the literature. The immunomodulatory protein APP has agglutinating activity in vitro, raising theoretical sensitization questions that have not been clinically observed. For healthy individuals consuming culinary amounts, cloud ear fungus has an excellent long-term safety record — the antiplatelet effect is the one pharmacological action that requires awareness.
What Makes Cloud Ear Fungus (Auricularia polytricha) Remarkable?
Cloud Ear Fungus presents several biological features that are genuinely unusual, most of which receive no attention in standard culinary or foraging resources.
Ancestral basidial architecture. The fruiting body of Auricularia polytricha bears basidia (spore-producing cells) that are transversely septate — divided into four compartments by three septa. Most familiar mushrooms have undivided (holobasidiate) basidia. The transversely septate tubular basidium of Auricularia is considered one of the most ancestral basidial types in the entire Basidiomycota, representing a window into the evolutionary origin of sexual reproduction in the most species-rich fungal phylum. This ancient architecture is visible under any student microscope and distinguishes Auricularia from every other jelly-fungus genus.
Desiccation-rehydration resilience. The gelatinous matrix of the fruiting body — composed largely of high-molecular-weight polysaccharides — contracts to a glass-like solid on drying and expands back to near-original dimensions on rehydration, with structural integrity preserved across multiple dry-rehydrate cycles. This property is commercially exploited (dried cloud ear stores indefinitely; rehydrates in 15–20 minutes) and ecologically important — field specimens can survive drought and revive with the return of rain. The mechanism is analogous to the desiccation tolerance of certain resurrection plants, but in a fungal fruiting body context.
The melanin developmental switch. Transcriptomic data from the fruiting body reveals that tyrosinase — the enzyme that produces melanin — is dramatically upregulated specifically during fruiting body development compared to mycelium. The white mycelium produces essentially no melanin; the dark brown fruiting body produces substantial amounts. This transcriptionally controlled developmental color switch is a model for understanding fungal melanogenesis and has prompted interest in the fruiting body melanin as a cosmetic and biomedical ingredient.
The cultivation antiquity record. The Tang Ben Cao (~600 AD) describes deliberate cultivation of Auricularia — making it arguably the first mushroom known to be farmed by humans, predating formal cultivation records for shiitake and most other edible species by centuries. The modern commercial cultivation industry in China, Taiwan, and Southeast Asia is thus built on over 1,400 years of continuous agricultural tradition, an extraordinary depth of practical knowledge base for any cultivated organism.
The name that covers three species. For over 100 years, mycologists in Asia and the West applied the name A. polytricha to what turned out to be multiple distinct organisms — including A. cornea (the primary Asian cultivated species), A. nigricans (the formal accepted name for the Americas type), and potentially others. This convergent morphological "solution" — multiple species independently evolving the same ear-shaped gelatinous fruiting body — reflects strong evolutionary pressure toward a particular architecture in wood-rotting jelly fungi, and it was only exposed through molecular phylogenetics in the 2010s.
Frequently Asked Questions About Cloud Ear Fungus (Auricularia polytricha)
What is the difference between cloud ear fungus, wood ear mushroom, and black fungus?
These three names are used inconsistently across markets and recipes, but here is the most accurate breakdown. "Cloud ear fungus" most specifically refers to Auricularia polytricha and is the name most associated with the smaller, thinner, more delicate product used in Chinese cuisine. "Wood ear mushroom" is applied more broadly across the entire Auricularia genus, including A. auricula-judae (Jelly Ear). "Black fungus" is a retail and packaging term applied non-specifically to A. polytricha, A. cornea, and A. heimuer interchangeably. In practice, the dried product sold as cloud ear in most Western markets is A. polytricha or A. cornea; the two are functionally interchangeable in culinary use but are distinct species scientifically.
Why does cloud ear fungus expand so much when rehydrated?
The fruiting body's gelatinous texture comes from a matrix of high-molecular-weight polysaccharides that hold large amounts of water when hydrated. When dried, these polysaccharides collapse into a compact, glassy solid. On contact with water, they rapidly reabsorb moisture and restore the original three-dimensional structure — a process that can expand the dried fungus 4–6 times its dried volume in 15–20 minutes. The structural integrity is preserved through multiple dry-rehydrate cycles, making this one of the most shelf-stable culinary mushrooms available.
Is it safe to eat cloud ear fungus before surgery or while taking blood thinners?
No — this is the one genuine safety concern for this species. Cloud ear contains approximately 154 µg of adenosine per gram dry weight, which inhibits platelet aggregation via the adenosine A₂A receptor. This antiplatelet effect has been documented in human subjects at culinary consumption doses, with platelet function suppressed for 3–24 days after consumption. It should not be consumed in the days prior to surgery or invasive procedures, and caution is warranted for anyone taking anticoagulant or antiplatelet medications such as aspirin, clopidogrel, or warfarin. Individuals with bleeding disorders should avoid it.
How is cloud ear fungus cultivated at home?
Cloud ear fungus is a fully saprotrophic white-rot fungus and one of the more cultivator-friendly edible species. The basic process is: expand liquid culture or agar wedges onto PDA or MEA agar; inoculate sterilized grain spawn; transfer colonized grain to pasteurized hardwood sawdust bags supplemented with rice bran at about 9% dry weight; colonize in darkness at 25°C with high CO₂ and 90–95% humidity for 25–38 days; then trigger fruiting by dropping temperature to 21–28°C, increasing fresh air exchange (lowering CO₂ below 500 ppm), and maintaining 85–90% humidity. Expect 4 flushes over approximately 3 months. Biological efficiency above 100% is achievable on well-supplemented substrates.
What does a cloud ear fungus liquid culture look like and how should I use it?
On agar, Auricularia polytricha mycelium grows white to grey-white with a slightly glossy, honeycomb-like surface texture. It is notably fast — colonizing a 100mm plate in approximately 4–5 days at 77°F (25°C). Because of this speed, subculture early from the leading edge of the colony at 3–5 days to maintain youthful, vigorous mycelium. The liquid culture syringe is primarily used to inoculate sterilized grain spawn or to establish fresh agar plates for culture maintenance. It can also be used for submerged fermentation to produce mycelial biomass for polysaccharide extraction.
Why do studies refer to different scientific names for cloud ear fungus?
Two separate issues create the name confusion. First, in 2013, molecular analysis confirmed that Auricularia polytricha is formally a synonym of the older name Auricularia nigricans (Sw.) — the accepted scientific name per current taxonomy. Most commercial and culinary sources continue to use A. polytricha, which is the name on this product. Second, the vast majority of cultivation and bioactivity research published under "A. polytricha" from China and other Asian countries most likely describes Auricularia cornea — a distinct species that was called "A. polytricha" throughout Asia for over 100 years before molecular analysis clarified the distinction in 2021. The two species are functionally similar for cultivation purposes but are taxonomically distinct.
Also available as a culture plate from Out-Grow.
Cloud Ear Fungus (Auricularia polytricha) Culture Plate