Cinnamon Cap Mushroom (Hypholoma sublateritium)
Cinnamon Cap Mushroom (Hypholoma sublateritium)
Cinnamon Cap Mushroom (Hypholoma sublateritium), also widely known as Brick Cap, is a wood-decay fungus native to temperate forests across North America, Europe, and East Asia. It fruits in dense, brick-red clusters on hardwood stumps and logs from late autumn into early winter — often long after competing mushrooms have finished. In Japan it has been eaten and cultivated as Kuritake for generations; in its genome, researchers discovered a gene that belongs to the bioluminescence pathway of glowing mushrooms, even though this species doesn't glow.
Hypholoma sublateritium (Fr.) Quél. (= H. lateritium) — Family Strophariaceae — Order Agaricales
Cinnamon Cap Mushroom (Hypholoma sublateritium) occupies a distinctive seasonal niche: it is among the last edible mushrooms of autumn in the northeastern United States, fruiting in dense clusters after the first frosts have ended the season for most competitors. It is commercially cultivated in Japan under the name Kuritake (クリタケ), has been eaten in the northeastern US for generations, and has a sequenced genome that has yielded some genuinely unusual findings — including a characterized anticancer compound biosynthetic pathway, and a gene from the bioluminescence pathway of glowing fungi sitting silently in its DNA. One important note before diving in: "cinnamon cap" is the name Out-Grow uses for this species, and it describes this mushroom well — but the same common name is also applied by at least one major vendor to an entirely different species, Pholiota adiposa. This article is about Hypholoma sublateritium specifically.
Interested in this species? Out-Grow carries a liquid culture.
Cinnamon Cap Mushroom (Hypholoma sublateritium) Liquid CultureWhat Is the Cinnamon Cap Mushroom (Hypholoma sublateritium)?
Cinnamon Cap Mushroom (Hypholoma sublateritium) is a gilled wood-decay fungus in the family Strophariaceae — a family that also includes Psilocybe, Stropharia, Pholiota, and the deadly Galerina. The ecological breadth of this family is remarkable: it contains species ranging from choice edibles to deadly poisonous ones, which is why careful identification is essential before consuming any Strophariaceae. Within the genus Hypholoma, the Cinnamon Cap is most closely related to H. fasciculare (sulphur tuft, toxic) and H. capnoides (conifer tuft, edible) — the three forming a well-supported clade.
The species is a saprotroph — it feeds exclusively on dead wood, requiring no living host or mycorrhizal partnership. This is why cultivation is biologically feasible: it can be fed sterilized hardwood substrates in controlled conditions. Its wood-decay strategy is technically classified as white rot, though genomic analysis has revealed that its lignin-degrading enzyme repertoire is reduced compared to classic white-rot fungi, placing it in an intermediate decay category between white and brown rot. Both characteristics — saprotrophic lifestyle and intermediate decay strategy — have direct implications for how it performs on different cultivation substrates.
The "cinnamon" and "brick" in its common names both reference the same visual feature: the cap color. The cap center is distinctively brick-red, fading to pinkish or buff at the margin — a gradient that echoes the color of fired terracotta. The specific epithet lateritium (and the variant sublateritium) both derive from the Latin lateritius, meaning "of bricks" or "brick-colored." The currently accepted scientific name, per Index Fungorum, is Hypholoma lateritium (Schaeff.) P. Kumm. — though H. sublateritium remains in widespread use in research literature and vendor contexts.
How Is Cinnamon Cap Mushroom (Hypholoma sublateritium) Classified?
Full Taxonomy
| Rank | Name |
|---|---|
| Kingdom | Fungi |
| Phylum | Basidiomycota |
| Class | Agaricomycetes |
| Order | Agaricales |
| Family | Strophariaceae |
| Genus | Hypholoma |
| Accepted name | Hypholoma lateritium (Schaeff.) P. Kumm. |
| Widely used synonym | Hypholoma sublateritium (Fr.) Quél. |
Key Synonyms
| Synonym | Authority | Notes |
|---|---|---|
| Agaricus lateritius | Schaeff. 1774 | Basionym; earliest valid name |
| Agaricus sublateritius | Fr. 1838 | Basis for the widely used H. sublateritium |
| Hypholoma sublateritium | (Fr.) Quél. 1872 | Most widely used name in research and vendor contexts |
| Naematoloma sublateritium | (Fr.) P. Karst. | Common in older literature and Korean pharmacological studies |
| Dryophila sublateritia | (Fr.) Quél. | Older generic placement |
How Do You Identify Cinnamon Cap Mushroom (Hypholoma sublateritium)?
Key Morphological Parameters
Cinnamon Cap Mushroom (Hypholoma sublateritium) always grows in tight, dense clusters arising from a shared base at a wood source — a habit that immediately narrows identification. The cap is dry to slightly moist, convex when young and flattening with age. The most diagnostic field character is the color gradient: brick-red at the center, shading to pinkish, cream, or buff at the margin. Young caps are draped at the margin with wispy cortina-like veil fragments. The gills progress from pale gray through gray to purple-gray and finally dark purple-brown as spores mature — the absence of greenish or yellow tones in the gills is an important separator from H. fasciculare. The stem (4–12 cm long, 1–2 cm thick) is pale yellowish above the ring zone and reddish-brown below, often contorted due to the clustered growth habit; it characteristically bruises or stains yellow.
The spore print is purple-brown. This is the single most important safety character for this species — take it seriously. Microscopically, the spores are 6–7 × 3–4 µm, ellipsoid, smooth, thin-walled, with an obscure germ pore, yellowish in KOH. Chrysocystidia (pleuro-chrysocystidia) are abundant and fusoid-ventricose to mucronate — a characteristic microscopic feature of this genus. Clamp connections are present, consistent with the Strophariaceae family.
Lookalike Species
Galerina marginata (Deadly Skullcap) — DEADLY
Contains amatoxins (α-amanitin) identical to death cap. Cap brown/tawny, not brick-red; ring fragile and single; rusty-orange spore print vs. purple-brown. Can grow on the same hardwood, same stump, same autumn. This distinction must be confirmed before every collection.
Hypholoma fasciculare (Sulphur Tuft) — TOXIC
Cap sulfur-yellow to greenish-yellow (not brick-red); young gills have distinct greenish-yellow tones; intensely bitter taste throughout. Causes significant gastrointestinal symptoms and occasional neurological effects. The bitterness of H. fasciculare is unmistakable — but do not rely on taste alone.
Hypholoma capnoides (Conifer Tuft) — Edible
Cap tawny/brownish with less red; grows exclusively on conifers (never on hardwood); gills smoky-gray with no purple tones; generally smaller. Substrate alone rules out confusion in most field situations — check the tree species.
Pholiota spp.
Often have scaly or sticky/viscid caps; brown to rusty-brown spore print (not purple-brown); ring typically more prominent. Several Pholiota species grow in autumn clusters on hardwood. Spore print color reliably separates them.
Armillaria spp. (Honey Fungus)
White spore print; distinct, persistent ring; different cap texture (often with small scales); generally paler caps. White spore print immediately separates from the purple-brown of H. sublateritium.
Where Does Cinnamon Cap Mushroom (Hypholoma sublateritium) Grow?
Cinnamon Cap Mushroom (Hypholoma sublateritium) is a saprotrophic wood-decay fungus — it grows on dead hardwood, extracting carbon and nutrients from the dead wood substrate without requiring any living plant partner. It causes a form of intermediate wood rot: technically classified as white rot, its genome contains fewer lignin-degrading enzyme genes than classic white-rot fungi, giving it a decay strategy closer to an intermediate between white and brown rot. The mycelium forms hyphal cords and rhizomorphs in soil between buried wood pieces — an unusual behavior for Agaricales that allows it to spread through buried debris fields and can produce fruitings some distance from an obvious wood source.
Host Associations
The Cinnamon Cap grows in dense clusters on dead hardwood logs, stumps, and buried roots. Documented hosts include oak (Quercus), chestnut (Castanea), beech (Fagus, especially in Europe), poplar and cottonwood (Populus), hickory (Carya), and alder (Alnus). It is rarely if ever found on conifers — this is the primary ecological difference from its close relative H. capnoides. Fruitbodies can emerge from soil in areas rich in buried woody debris, sometimes appearing with no obvious dead wood visible at the surface.
Range and Seasonality
| Region | Status | Typical Season |
|---|---|---|
| Northeast North America | Common | October–December; persists after hard frosts |
| Midwest and adjacent Canada | Common | October–November |
| Britain and Ireland | Rather uncommon | July–October |
| Central Europe (Hungary, Germany) | Present | September–November |
| Japan (Kuritake) | Common; cultivated | Autumn–early winter |
| Korea | Present; studied | Autumn |
The cold-weather fruiting ecology is one of the most defining biological characteristics of this species. Fruitbodies emerge when most other autumn mushrooms have already finished, and they actively persist through light frosts that would terminate the season for most competing saprophytes. This late-season niche also reduces insect larval damage — a practical benefit for foragers seeking clean, undamaged specimens. In northeastern North America, seasoned foragers specifically seek it out in November and December as one of the last edible mushrooms of the year.
Can You Cultivate Cinnamon Cap Mushroom (Hypholoma sublateritium)?
Cinnamon Cap Mushroom (Hypholoma sublateritium) is cultivable — it requires no mycorrhizal partners and can be grown on dead hardwood substrate. It is commercially cultivated in Japan. That said, it presents real challenges compared to oyster mushrooms or shiitake: it requires cold fruiting temperatures (10–16°C / 50–60°F), is susceptible to contamination during spawn run, and produces more slowly on indoor blocks than most beginner-friendly species. Outdoor log cultivation with a multi-season fruiting pattern is the approach with the most documented success.
Spawn Run Conditions (Stamets 1993)
Fruiting Conditions (Stamets 1993 / Vendor Data)
The temperature requirement for fruiting is the most common point of failure in indoor cultivation. This species will not pin above approximately 18°C (65°F). Cultivators attempting to fruit at room temperature consistently report failure — a frustration well-documented in online cultivation forums. A dedicated cold space (refrigerator compartment, cold room, unheated basement in autumn) that can maintain 10–16°C is essentially required. This same constraint is why the species is primarily an autumn crop in both wild and cultivated settings: it is naturally triggered by the seasonal temperature drop.
Cultivation Approaches
Substrate Preparation
Hardwood sawdust (oak preferred) with optional wheat or rice bran supplementation (10–20% by weight). Supplementation accelerates colonization but increases contamination risk — a tradeoff requiring good sterilization. Full sterilization at 121°C is recommended; pasteurization is insufficient for supplemented blocks.
Inoculation with Liquid Culture
Inject liquid culture into cooled sterilized substrate using strict sterile technique. This species is described as susceptible to mold — liquid culture inoculation reduces contamination exposure compared to grain-to-grain transfers by minimizing handling steps. Work in still air or a flow hood.
Spawn Run
Incubate at 21–24°C, 95–100% humidity, minimal air exchange. Duration: 20–28 days for grain spawn, longer for sawdust or logs. After full colonization, allow a resting period of 14–28 days before attempting fruiting induction. Cold temperatures during fruiting provide some competitive advantage against mesophilic mold contaminants.
Fruiting Trigger
Drop temperature to 10–16°C. This is the essential trigger and cannot be bypassed. Introduce fresh air (1–2 exchanges/hour) and maintain 90–95% humidity. Light at 100–200 lux helps orient growth. Without the cold drop, pins will not form reliably regardless of other conditions.
Outdoor Log Cultivation
A Japanese patented method (Nagano Prefecture Forest Research Center) inoculates logs with simple spawn; logs are buried and fruit in situ for multiple seasons. Field & Forest Products recommends pressure-cooking or steaming log segments before inoculation, then partially burying outdoors. Oak is most widely recommended; alder, chestnut, poplar, and hickory also documented. First fruiting: as early as the first autumn, or up to several years post-inoculation.
Harvest
Harvest when caps are fully expanded but before gills become very dark and spore release begins. Younger specimens are generally milder and more tender; older specimens tend toward more bitterness and tougher texture. Cook thoroughly before eating — never consume raw. Individual sensitivity to Strophariaceae varies; try a small portion first.
About the Out-Grow Cinnamon Cap Liquid Culture
Out-Grow's Cinnamon Cap Mushroom (Hypholoma sublateritium) liquid culture is a 10cc syringe of viable mycelium ready to inoculate sterilized grain, hardwood sawdust blocks, or log segments. Liquid culture is the recommended inoculation method for this species because Hypholoma sublateritium is susceptible to mold contamination — LC inoculation reduces handling steps and contamination exposure compared to agar wedge transfers.
The JGI reference strain of this species (FD-334 SS-4) was cultured in YMG (yeast-malt-glucose) liquid media in biosynthetic research studies, confirming that standard rich liquid media support growth. Liquid culture can be used for: grain spawn production for log or sawdust block inoculation; expansion onto agar plates (MEA, MYPA, or PDYA) for working culture maintenance; experimental log inoculation; and mycelial biomass production for compound extraction or research. Store refrigerated until use and inoculate promptly for best viability.
What Bioactive Compounds Does Cinnamon Cap Mushroom (Hypholoma sublateritium) Contain?
Cinnamon Cap Mushroom (Hypholoma sublateritium) has a published whole-genome sequence (JGI strain FD-334 SS-4, GCA_000827495) that has been mined in multiple studies for biosynthetic gene clusters. The result is one of the more chemically characterized autumn edible mushrooms in the research literature — though all bioactivity data is in vitro or from invertebrate models, with no human clinical evidence.
Is Cinnamon Cap Mushroom (Hypholoma sublateritium) Safe to Eat?
Cinnamon Cap Mushroom (Hypholoma sublateritium) is considered edible and is commercially cultivated and widely eaten in Japan, valued in northeastern North American foraging communities, and consumed in Korea. It has a long history of safe consumption in these regions when correctly identified and properly cooked. The primary safety concern is not intrinsic toxicity — it is misidentification, particularly confusion with Galerina marginata.
An unusual cultural discrepancy exists: European field guides frequently label this species inedible or even poisonous, while North American and Asian sources consider it a good edible. No published study has identified a toxic compound in H. sublateritium that would explain the European caution, and the basis for this geographic difference in assessment has never been rigorously investigated. It may reflect historical confusion with the toxic H. fasciculare, differences in preparation methods, or genuine but undocumented individual sensitivity variation.
A note on compound-level safety: cerevisterol, a sterol isolated from the fruiting body in the 2019 Szeged study, showed significant toxicity in bdelloid rotifer invertebrate assays. This finding has unknown relevance to human consumption — rotifers are not appropriate mammalian toxicology surrogates — but the absence of poisoning reports from Japan's decades of commercial cultivation and consumption is reassuring practical evidence of safety at normal serving sizes when cooked. Always cook thoroughly; never consume raw; start with a small portion on first trial.
What Makes Cinnamon Cap Mushroom (Hypholoma sublateritium) Remarkable?
A Broken Bioluminescence Gene
The H. sublateritium genome encodes hsPKS — hispidin polyketide synthase, the enzyme central to the bioluminescence pathway of glowing fungi. The species doesn't glow. Yet when researchers expressed this gene in yeast (2023 study), it produced dim bioluminescence when supplied with the right substrate. Whether an ancestor of this edible autumn mushroom once glowed in the dark is a genuinely open evolutionary question.
An Anticancer Compound BGC in an Edible Mushroom
Clavaric acid — a specific inhibitor of the Ras farnesylation pathway (IC₅₀ 1.3 µM) — is produced by a mushroom eaten in Japan for generations. The biosynthetic gene cluster is characterized, registered in MIBiG (BGC0001248), and the genes have been successfully manipulated to boost yields 32–97%. The Ras pathway is one of oncology's most pursued drug targets. The compound exists in an edible autumn fungus.
15 BGCs Shared with a Toxic Relative
Comparative genomics of H. sublateritium and H. fasciculare (the toxic sulphur tuft) identified 15 pairs of orthologous biosynthetic gene clusters — nearly identical secondary metabolite machinery between an edible and a toxic species. What makes one species safe to eat and the other cause vomiting and neurological symptoms is, at the biosynthetic gene level, still uncharacterized.
Underground Hyphal Highways
Unlike most cultivated Agaricales, H. sublateritium forms hyphal cords and rhizomorphs — thick, root-like strands of aggregated mycelium — in soil between buried wood pieces. This is unusual behavior that allows the fungus to spread between disconnected wood fragments and produce fruitings at some distance from an obvious substrate. Outdoor cultivation patches can potentially expand beyond inoculation sites.
High Wild Genetic Diversity
Natural Japanese Kuritake populations show high mitochondrial DNA variability — a finding relevant to cultivation breeding. Commercial Agaricus and Pleurotus strains typically show genetic bottlenecks from repeated propagation of a few successful lines. The wild H. sublateritium gene pool remains largely unscreened for cultivation performance, flavor, yield, or compound content — an unexploited resource.
Late-Season Frost Survivor
Fruiting in October through December, after hard frosts end the season for most competing saprophytes and insect larvae, is a distinct ecological strategy. Reduced competition at low temperatures — both from other fungi and from insect larvae that damage warmer-season fruitbodies — is a plausible adaptive advantage. In the northeastern US, this is the mushroom foragers seek out specifically because everything else has stopped.
Frequently Asked Questions About Cinnamon Cap Mushroom (Hypholoma sublateritium)
What is the difference between cinnamon cap and brick cap mushroom?
They are the same species — Hypholoma sublateritium. "Brick cap" is the more widely established common name in field guides and foraging literature, referencing the brick-red cap center. "Cinnamon cap" is also used, including by Out-Grow, and equally describes the warm reddish-brown coloration. One important caveat: "cinnamon cap" is also applied by at least one major vendor to Pholiota adiposa (chestnut mushroom), a completely different species. Whenever you see "cinnamon cap," confirm the scientific name to be certain which organism is being referenced.
Why are there two scientific names — H. sublateritium and H. lateritium?
Both names refer to the same species. Agaricus lateritius was described by Schaeffer in 1774; Agaricus sublateritius was described by Fries in 1838 from the same organism. Under the International Code of Nomenclature, the earliest epithet has priority, making Hypholoma lateritium (from 1774) the technically correct name. However, H. sublateritium accumulated decades of usage in North American mycology and in scientific research — including the clavaric acid biosynthesis papers — and remains in widespread use. You may also encounter the older name Naematoloma sublateritium in Korean pharmacological studies. Index Fungorum ID: 455825 covers both.
How do I safely distinguish Cinnamon Cap from Galerina marginata?
Take a spore print every time. Place the cap gills-down on white paper for 4–6 hours: Cinnamon Cap produces a purple-brown print; Galerina marginata produces a rusty-orange print. The difference is unambiguous. Additional separation characters: the Cinnamon Cap cap is brick-red at center, fading to buff at the margin; G. marginata is tawny brown, fading from the center outward. The Cinnamon Cap grows in very dense clusters; G. marginata tends toward smaller clusters or solitary growth. Never collect one without the other's separation confirmed by spore print — they can grow on the same stump in the same season.
What does Cinnamon Cap taste like and how should it be cooked?
Young, fresh specimens are mild with a slightly nutty flavor and firm texture. Older specimens — particularly those with very dark gills — tend toward bitterness. The Forager Chef notes that bitterness is not universal and that well-selected fresh specimens are reliably good. Always cook thoroughly; raw consumption is inadvisable. Pickling is a popular preparation in Japan and is noted by Mushroom Mountain as particularly well-suited to this species. Individual sensitivity to Strophariaceae varies — start with a modest portion on first consumption.
Can Cinnamon Cap be grown indoors, and what is the main challenge?
Indoor cultivation is possible but requires cold fruiting temperatures (10–16°C / 50–60°F) — the single most common barrier. This species will not reliably pin above approximately 18°C regardless of other conditions. A dedicated cold space is essentially required: a cold room, unheated basement in autumn, or a modified refrigerator compartment. Outdoor log cultivation is generally more forgiving — inoculated and buried oak logs can fruit for multiple consecutive seasons once established. No peer-reviewed study has published controlled yield or biological efficiency data for this species on any substrate; all figures are practitioner-grade estimates.
What is clavaric acid and does eating Cinnamon Cap provide cancer benefits?
Clavaric acid is a triterpenoid produced by H. sublateritium that inhibits the enzyme Ras farnesyl-protein transferase (FPTase) in laboratory conditions, with an IC₅₀ of 1.3 µM. The Ras farnesylation pathway is important in many human cancers, making FPTase a validated drug target. The compound has been characterized at the biosynthetic gene level and is sold as a research reagent. However, all evidence is in vitro enzyme inhibition — there are no animal model studies, no pharmacokinetic data, no bioavailability data, and no human clinical trials for clavaric acid or any compound from this species. The interesting biochemistry does not translate to a health claim about eating the mushroom.
Also available as a culture plate from Out-Grow.
Cinnamon Cap Mushroom (Hypholoma sublateritium) Culture Plate