Maitake (Grifola frondosa)
Maitake (Grifola frondosa)
Maitake (Grifola frondosa) is a large, cauliflower-like polypore native to the temperate forests of East Asia, Europe, and eastern North America, forming cascading rosettes of fan-shaped caps at the base of old oak trees. It is among the most celebrated medicinal mushrooms in Japanese and Chinese traditional herbology — known in Japan as "the dancing mushroom" — and the source of D-fraction beta-glucan polysaccharides with documented immunomodulatory activity in clinical research. The hen of the woods, as it is called by North American foragers, is commercially cultivated in Japan and China but remains one of the more demanding species to grow, requiring precise environmental control and carefully selected strains to fruit reliably.
Grifola frondosa (Dicks.) S.F. Gray, 1821 — Grifolaceae — Polyporales
Maitake (Grifola frondosa), also known as hen of the woods, is a polypore mushroom that grows in overlapping fan-shaped clusters from a shared base at the roots of large oaks across the Northern Hemisphere. It is simultaneously a prized culinary mushroom, a subject of serious pharmaceutical research for its beta-glucan compounds, and one of the more challenging species for cultivators to master. The science behind maitake is richer and more contested than most popular content acknowledges — and understanding that depth is what separates a well-informed grower or forager from someone working with half the picture.
Interested in this species? Out-Grow carries a liquid culture.
Maitake (Grifola frondosa) Liquid CultureWhat Is Maitake (Grifola frondosa)?
Maitake (Grifola frondosa) is a wood-rotting basidiomycete fungus that produces one of the most visually striking fruiting bodies in temperate forests. The name "maitake" derives from Japanese and literally means "dancing mushroom" — a reference to the legend that Buddhist nuns and woodcutters danced for joy upon discovering it growing on a mountain trail. In feudal Japan, it could reportedly be traded weight-for-weight in silver.
The fruiting body emerges from an underground sclerotium (a dense, potato-sized storage structure attached to the host tree's root system) and expands into a rosette of dozens to hundreds of individual fan-shaped caps, all arising from a shared branched stem. Exceptional specimens in Japan have been documented at over 50 kilograms — earning the species its secondary Japanese title, "King of Mushrooms."
The counterintuitive ecology: Maitake behaves as both a parasite and a saprobe. It can infect living trees through the root system, causing white butt rot that hollows out the tree's base over years while leaving it standing — a slow strategy that maximizes the duration of nutrient availability for the fungus. A 2024 study found that G. frondosa employs a two-stage decay strategy: in the first two years it preferentially degrades lignin and deacetylates hemicellulose, then shifts to cellulose breakdown in year three.
In North America, hen of the woods is the dominant common name among foragers. In Japanese supplement markets, maitake leads. Both terms have substantial independent search volume, and both refer to the same species — though recent molecular work has revealed that what we call "Grifola frondosa" may actually be a complex of two or three distinct biological species, with North American, Asian, and European populations genetically separable. This taxonomic situation is unresolved and has direct implications for researchers working with voucher material or studying the species' chemistry.
How Is Maitake (Grifola frondosa) Classified?
The accepted name Grifola frondosa (Dicks.) S.F. Gray was established in 1821, when S.F. Gray transferred the species from Boletus frondosus, the original 1785 description by Dickson. The genus name Grifola comes from the Greek griphos, meaning "intricate" or "braided," referring to the interlaced structure of the fruiting body. The species epithet frondosa is Latin for "leafy" or "covered with leaves," describing the overlapping frond-like caps.
| Rank | Classification |
|---|---|
| Kingdom | Fungi |
| Phylum | Basidiomycota |
| Subphylum | Agaricomycotina |
| Class | Agaricomycetes |
| Order | Polyporales |
| Family | Grifolaceae (Index Fungorum) / Meripilaceae (GBIF) |
| Genus | Grifola |
| Species | Grifola frondosa (Dicks.) S.F. Gray, 1821 |
| MycoBank / IF ID | 362177 |
Family placement discrepancy: Index Fungorum (the primary nomenclatural authority for fungi) places G. frondosa in Grifolaceae. GBIF and Wikimedia taxonomy list it under Meripilaceae. NCBI uses a third placement (Schizophyllaceae) which NCBI itself flags as non-authoritative. For this article, Grifolaceae is used as the primary family, following Index Fungorum.
The Cryptic Species Problem
A 2002 molecular phylogenetic study published in Mycologia (Shen et al., 94(3):472–482) analyzed 51 isolates using ITS/5.8S rDNA and β-tubulin sequences and found strong phylogenetic support for a species partition separating eastern North American and Asian isolates. The single European isolate was distinct from both. A 2023 genus-level study confirmed that the Northern Hemisphere clade (G. frondosa, growing on Fagaceae and Betulaceae) is sister to a Southern Hemisphere clade of four taxa.
Despite this molecular evidence — which has been replicated by subsequent work — no formal taxonomic revision has been published. The species as currently circumscribed is likely a complex of at least two, possibly three, cryptic lineages. Commercial cultivation strains were shown to cluster within the Asian clade. This has no practical consequence for the forager (all populations are edible), but it matters significantly for researchers comparing bioactive chemistry or cultivation genetics across geographic sources.
How Do You Identify Maitake (Grifola frondosa)?
Maitake (Grifola frondosa) is one of the easiest large polypores to identify in the field, with no dangerous lookalikes in North America or Europe. The key characters are the compound rosette form at the base of living or dead hardwood trees, the small angular pores on the undersurface, white spore print, and white flesh that does not stain when cut.
Macroscopic Description
Young specimens are dark gray-brown with fine fibrils and form compact, brain-like clusters. Field observers note that well-hydrated specimens can quadruple in size in under a week. Over-mature specimens yellow noticeably at the margins and become leathery and tough, eventually inedible. An uncommon near-pure white form occurs occasionally in the wild.
Lookalike Species
Meripilus sumstinei — Black-Staining Polypore
Same overall rosette form at tree base, similar coloring. Key difference: fronds are 12–19 mm thick vs. 3–6 mm in maitake, and flesh turns dark black when bruised or cut. Edible but not preferred. North American equivalent to M. giganteus.
Bondarzewia berkeleyi — Berkeley's Polypore
Large compound polypore at base of oaks, similar general appearance. Differences: individual caps much larger and paler cream-tan; flesh extremely thick and fibrous; no underground sclerotium; different spore ornamentation. Edible but often bitter.
Polyporus umbellatus — Umbrella Polypore
Compound polypore with white spore print. Key difference: individual caps are round and circular with a central depression (funnel-shaped when young), not fan-shaped; individual caps only 1–5 cm; typically spring-fruiting; much less massive overall. Edible and choice.
Laetiporus sulphureus — Chicken of the Woods
Shares the general "cluster at a tree base" gestalt only. Unmistakably bright orange-yellow coloring; shelf/bracket form growing above ground, not a ground-level rosette. Edible, but causes GI reactions in some people.
Safety note: No poisonous lookalikes exist for Grifola frondosa in North America or Europe. This is one reason it is frequently recommended for beginning foragers. The most likely confusion is with Meripilus sumstinei, which is identifiable by its blackening flesh reaction — a reliable field test.
Where Does Maitake (Grifola frondosa) Grow?
Maitake (Grifola frondosa) has a circumpolar Northern Hemisphere distribution across temperate forests. It requires old, large, veteran trees — young trees rarely host it. The primary host is Quercus (oak), particularly large old-growth specimens. It has also been documented on maple (Acer), chestnut (Castanea), beech (Fagus), elm (Ulmus), and occasionally large conifers.
| Region | Distribution | Peak Season |
|---|---|---|
| North America | Eastern U.S. and Canada; documented west to Idaho | September–October |
| Europe | Temperate hardwood zones from Mediterranean north to southern Fennoscandia | August–October |
| East Asia | China and northeastern Japan; core of commercial production | Late summer–autumn |
The fruiting body grows from an underground sclerotium attached to the host tree's root system, which is why the same tree base produces specimens year after year — the mycelium persists through winter underground while the fruiting body dies back. Foragers document that oaks with one infected specimen often have neighboring trees infected as well, since root grafting between neighboring oaks can spread the mycelium through an entire grove.
Conservation Status
| Jurisdiction | Status | Notes |
|---|---|---|
| Global (IUCN) | Least Concern | Widespread circumpolar distribution |
| Europe (European Red List) | Near Threatened | Linked to veteran tree loss across the continent |
| Ukraine | Endangered (EN) | Criteria C2a(i); known from 40+ localities but declining |
| Germany, Slovakia, Poland | National Red Lists | Listed; varies by country |
The primary threat everywhere is loss of veteran and old-growth trees through commercial logging, "tidy" forestry management that removes standing deadwood, and agricultural land conversion. G. frondosa is not a generalist — it is specifically dependent on trees of large diameter and advanced age. This conservation reality is rarely discussed in popular content, which tends to focus exclusively on the global Least Concern status while ignoring the European Near Threatened and Ukrainian Endangered designations.
Can You Cultivate Maitake (Grifola frondosa)?
Yes — but with significantly greater difficulty than oyster mushrooms, shiitake, or lion's mane. Commercial cultivation was first achieved in Japan in the mid-1980s, with mass production following approximately five years later. By 1999, Japan produced roughly 40,000 metric tons annually. The core cultivation challenge is that a high percentage of wild-isolated strains do not fruit reliably under artificial conditions, and even among strains that do fruit, performance varies dramatically. This is not a simple species to cultivate and requires more environmental control precision than most gourmet species.
Substrate
The standard substrate is hardwood sawdust (oak preferred) supplemented with wheat bran, typically in a 78:20:2 ratio (sawdust:bran:CaCO₃ — calcium carbonate, used to buffer pH) with substrate moisture content of 60–63%. Sterilization at 121°C for at least 60 minutes is required. A 2018 peer-reviewed study using a simplex-lattice design found that an optimized corn cob formulation produced a biological efficiency (the percentage of substrate weight converted to mushroom) of 44.91% — a 38.53% increase over the control sawdust formula. For comparison, oak sawdust plus corn bran produces approximately 35.3% BE. Avoid coffee spent grounds as a substrate — peer-reviewed research found it inhibits mushroom production.
Spawn Run Conditions
The spawn run is followed by a mandatory dormancy period — the species requires a temperature drop from spawn run temperatures to initiate fruiting. Without this signal, fruiting is inconsistent. In Japan, this is typically achieved through natural seasonal cooling. The long spawn run duration (up to 30+ days) represents an extended window of contamination risk compared to faster-colonizing species.
Fruiting Conditions
| Stage | Temperature | Humidity | CO₂ | Light | Duration |
|---|---|---|---|---|---|
| Primordia initiation | 10–15.6°C (50–60°F) | 95% | 2,000–5,000 ppm | 100–500 lux | 5–10 days |
| Stem formation | 10–15.6°C | 95% | 2,000–5,000 ppm | 100–500 lux | 10–14 days |
| Fruitbody development | 13–16°C (55–65°F) | 85–90% | <1,000 ppm | 500–1,000 lux | 14–21 days |
Light plays a molecular — not merely phototropic — role in fruiting. Peer-reviewed work published in Mycoscience (2019) confirmed that visible light triggers the tyrosinase gene tyr2, inducing melanin biosynthesis in the cell walls of primordia. This melanization event is mechanistically co-regulated with cap differentiation — which is why the gray-brown color of maitake caps is not incidental, and why adequate light is essential for normal cap development, not just orientation.
Fruiting Body Development Stages
Discoloration
Mycelium shifts from white to dark grey amorphous mass as it enters reproductive mode.
Primordium Formation
Dark grey mounds differentiate into distinct ball-like primordia under appropriate light and CO₂ signals.
Stem Emergence
Multiple stems with globular tips emerge from the base, beginning the characteristic branched structure.
Cap Unfurling
Petal-like sporulating fronds (caps) unfurl from each stem tip, forming the full rosette.
Strain Selection
Strain selection is arguably the most important variable in maitake cultivation. A peer-reviewed study comparing 23 genotypes from Asia, North America, and Europe found substantial variation in biological efficiency, quality, and crop performance — with the majority of wild-isolated strains not fruiting reliably under artificial conditions. Commercial production relies on a small number of selected, proprietary strains, with the best performers clustering in the Asian clade. This is one of the most practically important and under-documented aspects of the species for cultivators.
Agar Culture Behavior
On agar, G. frondosa produces white to off-white, longitudinally linear colonies that become thickly cottony on enriched media. The colony is non-rhizomorphic (no cord-like strands) and grows in an uneven, surge-based pattern — regions of the colony advance while others temporarily slow, producing an irregular outline. This asymmetric growth is considered a species-level characteristic and is not a sign of poor health. Peripheral edges of aging colonies develop light tawny-brown tones. Mature sawdust spawn develops rust-brown to orange-brown mottled zones with yellowish-orange metabolite exudation — also normal for this species. Preferred media: Malt Yeast Agar (MYA), Potato Dextrose Yeast Agar (PDYA), or Dog Food Agar (DFA).
About the Out-Grow Maitake Liquid Culture
Out-Grow's Maitake (Grifola frondosa) liquid culture is a 10cc syringe containing viable mycelium in a nutrient solution, genetically isolated for purity. Liquid culture serves well-documented applications for this species: inoculating sterilized grain spawn or hardwood sawdust substrate, expanding onto agar plates for strain banking, and producing mycelial biomass for research applications.
Submerged fermentation of G. frondosa is extensively documented in peer-reviewed literature — maximum biomass yields of 16.8 g/L and exopolysaccharide production of 5.3 g/L have been achieved under optimized bioreactor conditions. For cultivators, liquid culture eliminates the agar transfer steps of traditional culture expansion, reducing contamination risk during the early inoculation stages of what is already a contamination-sensitive species. Store refrigerated; inoculate sterilized substrate or agar within the viability window.
Contamination Risks
Trichoderma (green mold) is the primary contamination risk, as with most wood-loving species. Full sterilization at 121°C for minimum 60 minutes is essential. Burkholderia spp. bacteria isolated from G. frondosa cultivation environments have a severe inhibitory effect on mycelial growth. Priestia aryabhattai has been identified as the causative agent of bacterial spot disease in commercially cultivated maitake. Over-supplementation of substrate combined with excess moisture creates conditions for bacterial blotch.
What Bioactive Compounds Does Maitake (Grifola frondosa) Contain?
Maitake (Grifola frondosa) is one of the most chemically studied medicinal mushrooms. Its primary bioactive compounds are polysaccharides — particularly beta-glucans (glucose polymers linked by beta-glycosidic bonds) — but it also contains sterols, triterpenes, phenolic acids, and volatile aromatic compounds.
Protein-bound β-(1,3)(1,6)-glucan. Activates macrophages, T-cells, and NK cells. Oral administration as effective as intraperitoneal injection in mouse models. Basis for the SFDA-approved Chinese pharmaceutical.
Novel heteropolysaccharide. Upregulates CD80, CD86, CD83, MHC II on dendritic cells; increases IL-12 and TNF-α in a dose-dependent manner.
Distinct α-1,6-branched α-1,4 glucan. Antitumor activity in colon-26 and B16 melanoma mouse models via Peyer's patch activation of dendritic cells and macrophages.
Water-soluble glycoprotein. Studied for hypoglycemic effects. A 7-person uncontrolled pilot found blood glucose reductions in all participants — no control arm; preliminary only.
Primary sterol; UV precursor to vitamin D. Demonstrated mast cell degranulation suppression in a 2019 mouse allergy model. Content in dried mycelium: 5.80 mg/g dry weight (HPLC-measured).
Gallic acid and p-coumaric acid identified by HPLC-DAD (2025 study). Total phenolic content: 34.83 mg GAE/g. ABTS radical scavenging at 5 mg/mL comparable to L-ascorbic acid.
Documented anti-inflammatory and anticancer activities in preclinical models. Specific triterpene compounds have not been individually characterized to the degree seen in Ganoderma lucidum — a genuine research gap.
1-octen-3-ol and benzaldehyde identified as common volatiles by HS-SPME-GC-MS. No dedicated GC-olfactometry study has yet identified the specific odor-active compounds driving the characteristic earthy aroma.
Pharmaceutical milestone: A Grifola frondosa polysaccharide-based drug was approved by China's State Food and Drug Administration (SFDA) in 2010 as an adjunctive therapeutic drug for cancer treatment — administrable orally or by injection. This represents the most advanced regulatory outcome for any G. frondosa compound to date and distinguishes it from most fungal glycan drugs, which require injection.
Is Maitake (Grifola frondosa) Safe to Eat?
Maitake (Grifola frondosa) has no documented primary toxins and has a long history of food use in Japan and China without documented toxic effects from normal culinary consumption. It is generally regarded as safe when cooked. That said, several documented adverse events and interactions are worth knowing.
The most serious documented adverse event in the literature is a single case report of occupational hypersensitivity pneumonitis (lung inflammation) in a 49-year-old woman who worked on a maitake farm for three months. This is an occupational risk from repeated high-level spore exposure — not a consumption risk for home cooks or cultivators harvesting before full sporulation. Mild adverse events reported in a Phase I/II clinical trial included nausea, joint swelling, rash, and pruritus (itching) in 2 of 34 participants. Gastrointestinal discomfort at high doses has been informally reported.
Drug interactions to know: Maitake extracts have demonstrated blood glucose-lowering effects — additive hypoglycemia risk when combined with insulin or oral antidiabetics. Potential additive blood pressure-lowering effect with antihypertensive medications. The immunomodulatory activity of polysaccharides could potentially antagonize immunosuppressive drugs (e.g., cyclosporine, tacrolimus used in transplant patients). Cancer patients and immunocompromised individuals should discuss supplementation with their healthcare provider before use.
An important nuance from the Phase I/II clinical trial: maitake extracts produced both immune-enhancing and immune-suppressive effects at different doses — the dose-response curve was non-monotonic. This means the effect is not simply "immune boosting"; at certain dose levels, specific immune parameters were depressed relative to baseline. The popular claim that maitake "boosts immunity" does not capture this complexity.
The long history of safe culinary use applies to cooked fruiting bodies, not to concentrated pharmaceutical extracts. Extract concentrations used in pharmaceutical studies are substantially higher than dietary consumption. "No known toxic cases" for cooked culinary use does not automatically extend to high-dose extracts in vulnerable populations.
What Makes Maitake (Grifola frondosa) Remarkable?
The Underground Sclerotium
Maitake (Grifola frondosa) does not emerge directly from wood or soil — it grows from an underground, potato-sized sclerotium attached to the root system. Genomic and transcriptomic work has shown that oxidative stress from unfavorable environmental conditions triggers sclerotium formation, causing mycelia to fuse and compact into the dense storage structure. This explains why maitake returns to the same tree base year after year despite the fruiting body dying back: the sclerotium persists through winter, stores nutrients, and remains ready to produce a fruiting body when conditions are right the following autumn.
Scale: The King of Mushrooms
Specimens in Japan have reportedly reached over 50 kg (110+ lbs), earning the species its title. A field observer documented a single colony stretching nearly 15 feet around the base of a large oak. Even in the northeastern United States, finding a multi-kilogram specimen is not unusual in a good year on an established tree. The underground sclerotium can persist for decades, supporting annual fruiting from the same location.
Light as a Molecular Developmental Switch
Visible light does not merely trigger growth orientation in maitake — it operates as a molecular switch. The tyrosinase gene tyr2 is light-responsive; exposure triggers its transcription, with the TYR2 protein localizing specifically in the cell walls of primordia. This drives melanin biosynthesis that is mechanistically co-regulated with structural differentiation of the cap. The companion gene tyr1 is constitutively expressed (always on); it is tyr2 alone that responds to light. The gray-brown color of maitake caps is thus a direct consequence of a light-triggered developmental program.
Two-Stage Selective Wood Decay
A 2024 study described a genuinely unusual two-stage strategy: in years one and two, G. frondosa preferentially degrades lignin and deacetylates hemicellulose — effectively softening the wood matrix — before deploying cellulases in year three. This is more sophisticated than a simple "attack everything" strategy and suggests coordinated enzyme secretion regulation across a multi-year timeframe. The practical result: the host tree is progressively weakened over years, not killed suddenly, maximizing the duration of nutrient availability.
A Tetrapolar Mating System
A 2023 study confirmed the tetrapolar mating system of G. frondosa: both A and B mating-type loci must be compatible for sexual reproduction, generating four possible mating types and substantial genetic diversity. The mating-type A locus is on chromosome 1; the B locus is on chromosome 11 (encoding 6 pheromone receptors and 5 pheromone precursors). The study also documented segregation distortion — Mendelian ratios are not fully satisfied in offspring — adding complexity to deliberate breeding programs.
Mercury Binding Activity
A polysaccharide-peptide from G. frondosa (GFPP) was shown in rat models to accelerate blood mercury clearance — a 50% reduction in blood mercury within two days of acute mercury chloride administration. The N-terminal amino acid sequence responsible (APPGMHQKQQ) was characterized by LC-MS/MS. This unusual biological activity is not widely discussed in popular maitake content and represents a distinct compound class from the immunological polysaccharides.
What Does the Human Clinical Evidence Show for Maitake (Grifola frondosa)?
Human clinical evidence for maitake (Grifola frondosa) is limited. No large-scale randomized controlled trials have been published. The most rigorous published human study is an open-label Phase I/II dose escalation trial (Deng et al. 2009, Cancer Immunology, Immunotherapy) involving 34 postmenopausal breast cancer patients free of disease after initial treatment. The trial found no dose-limiting toxicity and a statistically significant association with immunological function — but the dose-response was non-monotonic, meaning intermediate doses both enhanced and suppressed specific immune parameters. No control arm was included; no disease outcome endpoint was measured.
Additional evidence comes from non-randomized case series (Kodama et al.) with no control arms, and a 7-person uncontrolled pilot study of the SX-fraction in type 2 diabetes patients that found blood glucose reductions in all participants — too small and uncontrolled to be conclusive. The animal model evidence across antidiabetic, antitumor, and anti-allergic applications is substantial and biologically plausible. The honest summary from the CAM-Cancer systematic review: there is limited evidence that maitake extracts can increase the functional capacity of monocytes and NK cells in cancer patients, but no clinical trial evidence for direct anticancer effects. Randomized controlled trials with disease outcome endpoints do not yet exist.
Frequently Asked Questions About Maitake (Grifola frondosa)
Is maitake the same as hen of the woods?
Yes. Maitake and hen of the woods are two common names for the same species, Grifola frondosa. "Maitake" (meaning "dancing mushroom" in Japanese) is the dominant term in supplement and health contexts; "hen of the woods" is the primary foraging and identification term used in North America. Both names are widely recognized and have genuine search volume — neither is informal or fabricated.
How hard is maitake to cultivate?
Significantly harder than oyster mushrooms, shiitake, or lion's mane. The core challenge is that most wild-isolated strains do not fruit reliably under artificial conditions, even with correct substrate and environmental parameters. Successful cultivation requires a well-selected fruiting strain, hardwood sawdust substrate properly sterilized, a temperature drop to trigger fruiting, and precise humidity and CO₂ management. Biological efficiency in peer-reviewed studies ranges from about 35% to 45% under optimized conditions — achievable, but requiring real attention to detail.
What is D-fraction and is there evidence it works?
D-fraction is a protein-bound beta-glucan extracted from maitake fruiting bodies. It has demonstrated immune cell activation in laboratory and animal studies, and a Phase I/II clinical trial in breast cancer patients found statistically significant immunological effects — but with a non-monotonic dose response and no disease outcome endpoint or control arm. A polysaccharide-based maitake drug was approved in China in 2010 as an adjunctive cancer treatment. The honest summary is that the preclinical evidence is strong, the mechanism is biologically plausible, and human randomized controlled trials with clinical endpoints do not yet exist.
Are there dangerous lookalikes for hen of the woods?
No — there are no poisonous lookalikes for Grifola frondosa in North America or Europe. The most likely confusion is with the black-staining polypore (Meripilus sumstinei), which is edible but not preferred. It can be reliably distinguished by cutting or bruising the flesh: it turns dark black within minutes, while maitake flesh remains white. Berkeley's polypore (Bondarzewia berkeleyi) and chicken of the woods (Laetiporus sulphureus) are visually distinct to anyone with basic foraging knowledge.
What does maitake liquid culture contain and what can you do with it?
A maitake liquid culture syringe contains viable Grifola frondosa mycelium suspended in a nutrient solution. It is used to inoculate sterilized grain spawn, hardwood sawdust substrate, or agar plates — replacing the agar transfer steps of traditional culture expansion. This is the primary commercial application of liquid culture for mushroom cultivation. Peer-reviewed submerged fermentation research has documented maximum biomass yields of 16.8 g/L and exopolysaccharide production of 5.3 g/L under optimized conditions, making liquid culture relevant for both cultivation spawn production and research applications.
Does maitake return to the same spot each year?
Yes — and this is one of its distinctive biological characteristics. Grifola frondosa grows from an underground sclerotium (a compact, potato-sized storage structure) attached to the host tree's root system. While the fruiting body dies back each year, the sclerotium persists through winter and supports new fruiting the following autumn. Experienced foragers often maintain secret "maitake trees" that they return to year after year. The mycelium can also spread to neighboring oaks through root grafts, so one productive tree often signals others nearby.
Also available as a culture plate from Out-Grow.
Maitake (Grifola frondosa) Culture Plate