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Humongous Fungus

The Humongous Fungus refers to a massive, genetically identical clone of the pathogenic fungus Armillaria ostoyae, commonly known as the honey mushroom, which forms the largest known living organism on Earth.^[1] This subterranean network of mycelium and rhizomorphs spans approximately 2,385 acres (965 hectares, or 3.7 square miles) in the Malheur National Forest within Oregon's Blue Mountains, near Prairie City.^[1]^[2] Estimated to weigh around 35,000 tons, it primarily exists underground as a web of thread-like hyphae that connect and communicate as a single entity, occasionally producing clusters of small, edible fruiting bodies (mushrooms with 2- to 5-inch caps) in autumn.^[1]^[3] Discovered through investigations beginning in the late 1980s, the extent of this fungal clone was mapped and confirmed in 1998 by a team of U.S. Forest Service scientists led by Catherine Parks, using DNA fingerprinting techniques such as restriction fragment length polymorphism (RFLP) and somatic incompatibility tests to verify its uniformity across the site.^[2]^[3] Initial observations in 1988 by forest manager Greg Whipple noted unusual tree mortality patterns in the Reynolds Creek and Clear Creek areas, prompting further study that revealed the fungus's role in widespread Armillaria root disease, which kills conifers over 20 to 50 years by invading roots and girdling trees.^[1] The organism's age is estimated at 2,400 to 8,650 years based on growth rates of 0.7 to 3.3 feet per year and genetic analyses, though some reports suggest it could approach 10,000 years, predating many human civilizations.^[2]^[1]^[4] As both a decomposer and aggressive pathogen, the Humongous Fungus plays a critical role in forest ecosystems by recycling nutrients from decaying wood while contributing to natural disturbance cycles that shape conifer stands.^[3] Its rhizomorphs—thick, black, cord-like structures—enable it to bridge gaps between host trees, transport water and nutrients, and survive environmental stresses like wildfires, highlighting the remarkable adaptability and scale of fungal life forms.^[1]^[2] Genetic studies, including those identifying rhizomorph-forming genes, have advanced understanding of Armillaria species' evolution and pathogenicity, with implications for forest management and biodiversity conservation.^[1] Despite its size, the fungus remains largely invisible above ground, challenging conventional notions of individuality in biology and underscoring the hidden complexity of microbial networks in natural environments.^[2]^[3]

Discovery and Identification

Initial Observations

The Humongous Fungus occupies a site in the Malheur National Forest within the Blue Mountains of eastern Oregon, at elevations ranging from 1,500 to 2,000 meters (4,900 to 6,600 feet).^[5] This region features a mixed coniferous forest dominated by Douglas fir (Pseudotsuga menziesii) and ponderosa pine (Pinus ponderosa), interspersed with grand fir (Abies grandis) and other species typical of the area's semi-arid climate, which includes cold, snowy winters and warm, dry summers.^[1] Initial field observations in the 1980s highlighted unusual patterns of tree mortality in the Reynolds Creek drainage, where widespread die-off affected stands of grand fir and other conifers, accompanied by classic symptoms of root rot such as wilting foliage, basal cankers, and resinous exudates at the soil line. Foresters noted clusters of honey-colored mushrooms—the fruiting bodies of the suspected pathogen Armillaria ostoyae—emerging in autumn around the bases of infected trees, extending across multiple acres without apparent gaps in distribution. These sightings suggested an interconnected infection rather than isolated incidents, raising concerns about a pervasive underground network.^[1]^[2]^[6] In 1988, U.S. Forest Service pathologist Greg Whipple conducted preliminary assessments in response to the escalating tree losses, observing the infection's seamless spread across diverse terrain and tree ages, lacking the discrete boundaries typical of smaller fungal outbreaks. Soil samples collected from the roots of dying trees that year consistently revealed dense white mycelial mats and black rhizomorphs permeating the substrate over expansive areas, indicating a unified and unusually extensive colony rather than multiple separate individuals. These early field-based insights laid the groundwork for further investigation into the scale of this Armillaria ostoyae occurrence.^[1]^[6]^[7]

Scientific Confirmation and Naming

The scientific confirmation of the Humongous Fungus began with systematic surveys in the late 1990s and early 2000s by a team of USDA Forest Service researchers from the Pacific Northwest Research Station, including plant pathologist Catherine G. Parks and colleagues B.A. Ferguson, T.A. Dreisbach, G.M. Filip, and C.L. Schmitt, based at laboratories in Corvallis and La Grande, Oregon.^[8] Their work focused on mapping Armillaria populations in a mixed-conifer forest spanning approximately 16,100 hectares in the Blue Mountains ecoregion of northeast Oregon, encompassing parts of the Malheur National Forest.^[9] To verify the extent and clonal nature of the fungus, the team collected over 100 isolates from symptomatic conifer roots, stumps, rhizomorphs, and soil samples across areas showing tree die-off patterns consistent with Armillaria root disease. Species identification was achieved through PCR-based molecular diagnostics, while genetic uniformity was confirmed using somatic incompatibility pairing tests—a method that assesses compatibility between fungal isolates to delineate distinct genets, akin to early DNA-based pairing approaches for clonal verification. These techniques demonstrated that samples from a vast area exceeding 1,000 acres exhibited identical genetic profiles, ruling out multiple independent infections and establishing the presence of a single expansive clone of Armillaria ostoyae.^[8]^[9] The key outcome was the identification of this A. ostoyae clone as a unified organism covering 965 hectares (2,385 acres), far surpassing previous records for fungal individuals. Follow-up surveys during the late 1990s and early 2000s refined the mapping, confirming the colony's boundaries through additional sampling and pairing tests, which highlighted its maximum span of about 3.8 kilometers between distant isolates.^[8] The research team informally referred to the clone as the "Humongous Fungus" in their 2003 publication, drawing inspiration from media coverage of a smaller Armillaria clone discovered in Michigan a decade earlier; it retains no formal binomial nomenclature beyond the species A. ostoyae. This naming emphasized its unprecedented scale while underscoring its role as a single, contiguous entity rather than disparate patches.^[8]^[1]

Biology and Characteristics

Species Taxonomy

The Humongous Fungus belongs to the species Armillaria ostoyae (Romagn.) Herink, classified within the kingdom Fungi, phylum Basidiomycota, class Agaricomycetes, order Agaricales, family Physalacriaceae, genus Armillaria. This taxonomic placement reflects its position among the basidiomycete fungi, characterized by spore-producing structures on club-like basidia. The species name ostoyae derives from Paul Ostoya (1904–1969), a French journalist and devotee of mycology who served as General Secretary of the Société Mycologique de France. A synonym, A. solidipes Peck, has been recognized in some classifications following epitypification efforts to resolve nomenclatural confusion; following a 2025 epitypification, A. solidipes Peck is confirmed as the valid name for the North American species, resolving prior confusion with A. ostoyae (Romagn.) Herink, which applies more to Eurasian populations.^[10]^[11]^[12]^[13]^[14] Armillaria ostoyae was originally described by French mycologist Henri Romagnesi in 1970 based on fruiting bodies collected from Douglas-fir (Pseudotsuga menziesii) in Oregon, later transferred to the genus Armillaria by Antonín Herink in 1973. This description highlighted its morphological traits distinguishing it from related species in the Armillaria mellea complex, a group of root pathogens. Genetic analyses have confirmed its identity through multilocus sequencing, resolving prior taxonomic ambiguities with European and Asian populations. The species' nomenclature underscores ongoing refinements in fungal systematics, prioritizing DNA-based phylogenetics over morphological variability alone.^[13]^[10]^[14] Genetically, A. ostoyae features a heterothallic, bifactorial mating system governed by multi-allelic incompatibility loci (A and B factors), requiring compatible haploid mycelia to fuse for reproduction. This fusion leads to a predominantly diploid, heterokaryotic mycelium—unique among many basidiomycetes—facilitating extensive clonal expansion via vegetative growth without immediate meiosis. Fruiting bodies, which are diploid, undergo meiosis to generate haploid basidiospores dispersed for sexual propagation, promoting genetic diversity while the persistent diploid phase supports long-term persistence in soil. This reproductive strategy enhances its adaptability as a pathogen.^[10]^[15]^[16] Evolutionarily, A. ostoyae exemplifies adaptations to a pathogenic lifestyle in temperate forest ecosystems, where it specializes in infecting woody roots through enzymatic degradation and resource acquisition. The genus Armillaria comprises approximately 40 species worldwide, distributed across temperate and boreal regions, but A. ostoyae predominates in North American conifer stands, such as those dominated by pines, firs, and spruces. Phylogenetic studies place it within a clade of aggressive root pathogens, with divergence from Eurasian relatives likely occurring post-glacial recolonization, enabling its clonal dominance in managed and natural forests.^[17]^[10]^[18]

Morphological Features and Growth Mechanism

The Humongous Fungus, a clonal colony of Armillaria ostoyae, primarily consists of an extensive underground mycelial mat known as a genet, formed by interconnected thread-like hyphae that create a continuous network penetrating soil and root systems.^[19] This mycelium forms thick, white mats of vegetative tissue, often described as mycelial fans, which can extend to depths of up to approximately 1 meter in soil associated with decayed roots, facilitating resource acquisition without frequent surface exposure.^[20] The hyphae, typically 2-5 micrometers in diameter, aggregate into this mat to form a diploid vegetative structure unique among basidiomycetes, enabling persistent underground expansion.^[19] A key feature enabling the colony's vast radial growth is the production of rhizomorphs, black, shoelace-like cords composed of bundled hyphae that function as conduits for transporting nutrients and water across long distances in soil.^[19] These rhizomorphs, which can reach thicknesses of 1–5 millimeters, exhibit a layered architecture with a melanized outer sheath for protection and internal channels for efficient translocation, allowing the fungus to bridge gaps between host roots.^[21]^[22] They drive colony expansion at radial growth rates of approximately 0.5 to 2 meters per year, depending on environmental conditions such as soil moisture and temperature, through apical and lateral tip extension. Genomic studies have identified evolutionarily young, lineage-specific genes upregulated in rhizomorphs, contributing to their formation and the fungus's expansive growth.^[23]^[24]^[25] Above ground, the fungus produces ephemeral fruiting bodies, commonly known as honey mushrooms, which emerge annually in the fall but are not required for the colony's ongoing survival as the perennial mycelial network persists independently.^[19] These basidiocarps feature yellow-brown to red-brown caps measuring 5-15 cm in diameter, initially convex and becoming flatter with age, often adorned with small dark scales and hygrophanous properties that cause paling upon drying.^[13]^[26] Reproduction in A. ostoyae occurs asexually through mycelial spread via hyphae and rhizomorphs, allowing clonal expansion of the genet without genetic recombination, as exemplified by the Humongous Fungus originating from a single initial infection event.^[19] Sexual reproduction involves the production of basidiospores from fruiting bodies under compatible mating conditions, though this contributes less to the persistence of large, established clones like the Humongous Fungus, where vegetative propagation dominates.^[19] The longevity of the Humongous Fungus is supported by physiological adaptations, including the secretion of lignin-degrading enzymes such as laccases and peroxidases, which enable the breakdown of complex lignocellulosic materials in tree roots to sustain nutrient uptake over centuries without relying on surface structures.^[19]^[27] These enzymes facilitate selective delignification, allowing the fungus to access carbon sources deep within woody substrates while minimizing exposure to environmental stresses.^[28]

Size, Age, and Distribution

Extent and Measurement

The Humongous Fungus, a clonal colony of Armillaria ostoyae in Oregon's Malheur National Forest, spans an estimated 2,385 acres (965 hectares), equivalent to about 3.7 square miles (9.6 square kilometers), establishing it as the largest known single organism by areal coverage.^[1] This vast underground network of mycelium occupies a contiguous area beneath the forest floor, surpassing other large fungal clones in documented extent.^[2] Quantifying the fungus's extent involved systematic grid-based soil sampling, typically at 100-meter intervals across suspected zones, where bait stations—such as wooden stakes buried in the soil—were used to isolate mycelial samples for analysis.^[29] These samples underwent genetic fingerprinting via DNA analysis to verify continuity and clonality, distinguishing the single genet from adjacent fungal individuals through markers like restriction fragment length polymorphisms or multilocus genotyping.^[2] Somatic incompatibility tests, where paired mycelia from different sites were grown together on agar to observe rejection or fusion, further confirmed the boundaries of the unified organism.^[30] Mapping the precise boundaries remains challenging due to the mycelium's irregular edges, shaped by heterogeneous soil conditions, nutrient availability, and competitive interactions with other soil microbes and roots.^[31] Undetected extensions are possible in unsampled areas, as the diffuse rhizomorphs can infiltrate beyond visible tree mortality patterns associated with the fungus.^[2] Repeat surveys since the initial mapping have documented gradual expansions, with the colony growing from approximately 400 acres (0.625 square miles) in 1988 to its present dimensions, including annual increments of several acres tracked via ongoing monitoring.^[7]^[32] Measurements emphasize areal coverage over volumetric estimates, as the mycelial mat is relatively shallow—typically less than 1 meter deep—and spreads horizontally through root systems and soil rather than forming dense, bulky structures.^[2] This approach highlights the fungus's expansive, two-dimensional dominance in its ecosystem.^[1]

Age Estimation Methods

The age of the Humongous Fungus, a massive clonal colony of Armillaria ostoyae in Oregon's Malheur National Forest, is primarily estimated through extrapolation of observed fungal growth rates to the colony's known spatial extent, which spans approximately 965 hectares. Researchers measure the expansion rates of the fungus's rhizomorphs—cord-like structures that facilitate underground spread—and mycelial growth in controlled settings, such as on buried wooden posts or in nutrient media like Petri dishes. These rates, typically ranging from 0.7 to 3.3 feet (21 to 100 cm) per year under favorable conditions, are then applied to the colony's diameter (about 3.8 km) to calculate minimum age.^[1] Initial surveys in the late 1980s yielded estimates around 2,400 years for early detected portions of the colony. Subsequent mapping in 2003 refined the colony's size and adjusted the age range to 1,900 to 8,650 years, with the upper bound assuming slower historical growth due to less optimal conditions.^[33] The consensus estimate remains around 2,400 years, representing the minimum age based on current growth rates observed in the field. This approach relies on the assumption of relatively uniform radial expansion from a central point of origin, calibrated against the colony's genotypic uniformity confirmed via somatic incompatibility tests and DNA analyses.^[33] Key uncertainties in these estimates stem from variations in growth rates over time, influenced by environmental factors such as climate fluctuations—including cooler periods like the Little Ice Age (roughly 1300–1850 CE), which may have slowed expansion—and potential multiple founding events from spores that could complicate the single-origin model. Additionally, the method does not account for periods of dormancy or irregular spread patterns due to soil heterogeneity or host availability. Despite these limitations, growth rate extrapolation provides the most direct evidence for the colony's longevity, establishing it as one of Earth's oldest known organisms.^[33]

Ecological Role and Impact

Pathogenic Effects on Trees

The Humongous Fungus, Armillaria ostoyae, primarily infects trees through root wounds or uninjured root tips, facilitated by its rhizomorphs that penetrate the bark and cortex before advancing into the xylem.^[18] Once inside, the fungus spreads via mycelial growth and produces cell wall-degrading enzymes, including laccase, which contribute to the breakdown of lignin and other structural components in the host tissue.^[34] This enzymatic activity enables the fungus to colonize the vascular system, disrupting water and nutrient transport.^[35] Symptoms of infection typically begin in the roots, where the fungus causes white rot characterized by stringy, spongy decay of the wood, often accompanied by black zone lines and white mycelial fans beneath the bark.^[36] Above ground, affected conifers exhibit crown wilting, thinning, and chlorosis, along with resin flow or exudation at the base of the trunk.^[37] Infected trees often lean or succumb to windthrow due to weakened root systems, with symptoms typically leading to mortality within several years after significant root damage, though the full disease progression can span 20 to 50 years depending on host and environmental factors.^[38] Armillaria ostoyae has a broad host range, infecting over 200 woody plant species worldwide, though it primarily targets gymnosperms such as Douglas-fir (Pseudotsuga menziesii), true firs (Abies spp.), and pines (Pinus spp.) in the Pacific Northwest forests of North America.^[18] In the Blue Mountains, it commonly affects grand fir (Abies grandis). While it can affect hardwoods, its virulence is notably higher on conifers, where it thrives in moist, coniferous-dominated ecosystems.^[39] Key virulence factors include the production of oxalic acid, which acidifies the soil and host tissues, lowering pH to enhance fungal nutrient uptake, such as iron and manganese, while suppressing competing microorganisms and host defenses.^[40] This acidification also facilitates calcium sequestration from cell walls, weakening structural integrity and promoting tissue invasion.^[22] In infected forest stands, A. ostoyae can cause significant tree mortality, with rates exceeding 20% in untreated conifer plantations and up to 40% or more in severely affected areas, leading to canopy gaps from clustered tree deaths.^[41]^[42] Such losses are particularly pronounced in young stands under stress, where root-to-root spread amplifies infection density.^[18]

Role in Forest Dynamics

The Humongous Fungus, a massive colony of Armillaria ostoyae, plays a pivotal role in nutrient cycling within forest ecosystems by decomposing dead roots and woody debris through white-rot decay, which breaks down lignin and cellulose to release essential nutrients such as nitrogen and phosphorus into the soil.^[18]^[43] This process enriches soil fertility, supporting the establishment of successor vegetation such as shrubs and understory plants in areas of tree mortality.^[18] As a saprophytic decomposer in addition to its pathogenic activity, the fungus sustains forest productivity by recycling organic matter, preventing nutrient lockup in undecayed biomass.^[43] In terms of disturbance regime, the fungus generates mosaic patterns of dead zones and canopy gaps across the forest floor, where scattered mortality centers create openings that disrupt uniform stand structure and promote biodiversity.^[18] These gaps allow understory plants, herbs, and younger trees to colonize, fostering habitat diversity for wildlife and shifting species composition toward more resilient understory communities.^[18] The resulting heterogeneity mimics natural disturbance events, enhancing overall ecosystem resilience by preventing monocultures and supporting a varied understory.^[44] The fungus interacts competitively with symbiotic mycorrhizal fungi, colonizing root spaces and potentially displacing them, which alters carbon allocation in host trees by redirecting photosynthates away from mutualistic networks toward pathogenic exploitation.^[18] This competition can reduce the efficiency of mycorrhizal nutrient uptake, influencing broader forest carbon dynamics and tree vigor. Over centuries, the colony's gradual expansion drives long-term forest succession by selectively killing early seral conifers like Douglas-fir (Pseudotsuga menziesii), favoring late-seral shade-tolerant conifers while sometimes maintaining infested patches through tolerant deciduous species.^[44] This selective pressure creates persistent disease centers that persist for decades in root systems, reshaping stand composition from climax forests toward more dynamic, mixed-age structures.^[18]^[44] Regarding climate resilience, the decaying wood produced by A. ostoyae infections enhances moisture retention in forest soils, potentially buffering localized drought effects by holding water in porous, decomposed material.^[45] However, the fungus itself shows vulnerability to warming trends and prolonged droughts, which stress host trees and expand infection opportunities while limiting rhizomorph growth and survival in drier conditions; recent studies (as of 2025) indicate increasing drought in the Pacific Northwest may alter these dynamics.^[46]^[18]

Comparisons and Significance

Comparisons to Other Large Organisms

The Humongous Fungus, an Armillaria ostoyae genet in Oregon's Malheur National Forest, holds the record for the largest organism by contiguous area, spanning 2,385 acres (965 hectares).^[2] By comparison, another notable fungal clone, an Armillaria gallica in Michigan's Upper Peninsula, covers only 91 acres (37 hectares), making it substantially smaller in spatial extent.^[47] In terms of biomass, the Humongous Fungus is estimated at 7,500 to 35,000 tons, though precise quantification remains challenging due to its subterranean mycelial structure.^[48] This surpasses the Michigan Armillaria's 440 tons and exceeds the biomass of certain plant clones, such as the quaking aspen (Populus tremuloides) genet known as Pando in Utah, which occupies 106 acres (43 hectares) and weighs approximately 6,000 metric tons (dry weight equivalent).^[49] Similarly, a massive Posidonia oceanica seagrass clone off Ibiza, Spain, extends over approximately 3,700 acres (15 km²) with substantial belowground biomass, contributing to high carbon storage in Mediterranean meadows, though exact totals for this clone are not fully quantified.^[50] Even larger by area is a Posidonia australis seagrass clone in Shark Bay, Australia, spanning approximately 200 km² (49,000 acres) as a single genetic individual, discovered in 2022.^[51] Biologically, the Humongous Fungus represents a fungal genet—a single genetically identical individual propagated through mycelial growth—contrasting with plant clones like Pando, where genetically uniform ramets (stems) are physically interconnected via an extensive root system.^[52] Animal analogues include ant supercolonies, such as those of the invasive Argentine ant (Linepithema humile), which form vast societies spanning thousands of kilometers across continents through cooperative nesting, though these are eusocial collectives rather than single genets.^[53] Measurement differences highlight these contrasts: fungal extent is determined by genetic continuity via DNA sampling of mycelia to confirm clonal identity, whereas plant clones like Pando are assessed through physical linkage of roots and rhizomes.^[54] For age, the Humongous Fungus is estimated at 2,400 to 8,650 years, rivaled by non-clonal trees like ancient bristlecone pines (Pinus longaeva), some exceeding 5,000 years.^[55] As of 2025, no larger fungal discoveries have been confirmed, though Armillaria stands in Siberian forests are under investigation for potential expansive clones.^[56]

Scientific and Cultural Importance

The Humongous Fungus, a massive clonal colony of Armillaria ostoyae in Oregon's Malheur National Forest, serves as a key model organism for investigating clonal longevity in fungi, with its estimated age of up to 8,650 years providing insights into long-term genetic stability and propagation strategies in perennial pathogens.^[1] Researchers have utilized it to explore genetic diversity within fungal populations, revealing lineage-specific innovations such as expanded gene families for lignocellulose degradation that enable its expansive growth and host colonization.^[25] Additionally, studies of this fungus illuminate climate impacts on forest pathogens, as rising temperatures and altered precipitation patterns exacerbate its spread while simultaneously stressing its conifer hosts, potentially shifting forest disease dynamics.^[56] Genomic sequencing projects in the 2010s, including chromosome-scale assemblies of A. ostoyae, have further highlighted its role in understanding fungal evolution and pathogenicity, with analyses identifying over 20,000 predicted genes adapted for wood decay and survival in temperate ecosystems.^[25]^[57] In the 2020s, ongoing research employs advanced monitoring techniques to track the colony's health and boundaries, including airborne LiDAR and orthoimagery to detect conifer mortality induced by root disease, achieving accurate mapping of affected trees in south-central Oregon forests.^[58] Metagenomic approaches complement these efforts by analyzing soil microbial communities associated with Armillaria root disease, offering insights into microbial interactions that influence pathogen persistence and forest regeneration.^[59] Culturally, the Humongous Fungus has captured public imagination through documentaries such as PBS's Oregon Field Guide (2015) and CBS's Sunday Morning (2021), which highlight its scale and subterranean life to underscore fungal contributions to ecosystems.^[7]^[60] It symbolizes the interconnectedness of forest networks in environmental education, inspiring discussions on belowground biodiversity and the hidden roles of fungi in sustaining life, as echoed in popular science literature like DK's Humongous Fungus (2021), which uses it to illustrate fungal diversity for broader audiences.^[61] The colony faces vulnerabilities from logging, which disrupts its host trees, fire suppression that favors its proliferation by reducing natural disturbances, and climate change, which may accelerate drought-induced tree mortality and alter its growth rates.^[62]^[56] While protected as part of the Malheur National Forest under U.S. Forest Service management, it lacks special conservation status, relying on general forest policies to mitigate threats.^[1] Public access to viewing sites is limited to safeguard the colony and surrounding habitat, with visitors advised to avoid dead trees to prevent hazards; the U.S. Forest Service promotes awareness through interpretive materials and outreach since the early 1990s, including videos and maps to educate on its ecological significance without direct site visits.^[48]^[63]

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Cumulative mortality from root disease for tree species in stumped plots is less than 4%; whereas, in the untreated plots it is more than 20% for most species.
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View of British Columbia's Southern Interior Forests Armillaria Root ...
Tree mortality usually begins about 5–7 years after stand establishment, peaks around age 12, and then declines, although mortality can continue throughout a ...
[38]
[PDF] Effects of forest management practices and environment on ...
However, some Armillaria species are predom- inately saprophytic, and may act to sustain forest produc- tivity by improving nutrient cycling through ...
[39]
[PDF] the behaviour and impacts of armillaria ostoyae in
Infected stumps are the initial sources of inoculum in plantations. Very young trees growing in contact with infected stumps are quickly killed. These small ...
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[PDF] Decaying wood in Pacific Northwest Forests: Concepts and Tools for ...
Moisture Retention. Water stored in large decomposing wood accelerates ... Decaying wood. Factors Influencing Regional Abundance of Decaying wood.
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Armillaria Pathogenesis under Climate Changes - MDPI
For many decades, root and butt rot caused by Armillaria mellea (sensu lato) has been a significant threat to the boreal forests of Europe and North America.
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This Humongous Fungus Is as Massive as Three Blue Whales
Oct 15, 2018 · An Armillaria found in eastern Oregon's Blue Mountains covers three square miles and may be over 8,000 years old, holding the current title for ...<|control11|><|separator|>
[43]
Author Names Oregon's Humongous Fungus as one of the Grossest ...
Nov 15, 2012 · This massive mushroom is estimated to weigh 7,567 to 35,000 tons, which would make it the largest living organism in the world. But that doesn't ...Missing: paper | Show results with:paper<|separator|>
[44]
How Aspens Grow - Forest Service - USDA
It is over 100 acres in size and weighs more than 14 million pounds. That is more than 40 times the weight of the largest animal, a blue whale. It has been aged ...
[45]
Seagrass meadows (Posidonia oceanica) distribution and ... - Nature
Jul 28, 2015 · In Spain, P. oceanica meadows were found to be widely present along the continental coastline and islands, with a measured area of 172,699 ha.
[46]
[PDF] Pando Clone (World's Largest Living Organism?) History and ...
It's a grove of quaking aspen trees spanning 106 acres near Fish Lake. Scientists call it an aspen clone, which is essentially a single plant comprised of ...Missing: biomass | Show results with:biomass
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The global expansion of a single ant supercolony - PMC - NIH
In this study, we conducted a global-scale analysis of the relationships among the world's largest supercolonies of Argentine ants. We performed inter- ...<|separator|>
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Unambiguous identification of fungi: where do we stand and how ...
Jul 10, 2020 · Here we provide a conceptual framework for the identification of fungi, encouraging the approach of integrative (polyphasic) taxonomy for species delimitation.
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Bristlecone pine | Tree, Age, Range, Facts, Oldest, & Lifespan
One individual, discovered in 2012, is estimated to be more than 5,060 years old, making it the oldest known non-clonal tree in the world! However, bristlecones ...
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The Bigger This Fungus Gets, the Worse We're Doing - The Atlantic
Aug 15, 2022 · Oregon's Armillaria expanse is the biggest individual recorded, but plenty of other ginormous specimens have been documented, including one ...Missing: comparison | Show results with:comparison
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Genome expansion and lineage-specific genetic innovations in the ...
Oct 30, 2017 · Genomes of Armillaria species were assembled to 103–319 scaffolds comprising 58–85 Mb and were predicted to contain 20,811–25,704 genes.
[52]
Chromosomal assembly and analyses of genome-wide ...
Here, we analyze recombination rate variation in the basidiomycete fungus Armillaria ostoyae, which is an aggressive pathogen on a broad range of conifers and ...
[53]
Identifying conifer mortality induced by Armillaria root disease using ...
We used high-density light detection and ranging (lidar), high-resolution aerial orthoimagery, and associated field observations to map individual tree health ...Missing: metagenomics 2020s
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Metagenomic approaches to determine soil microbial communities ...
Soil metagenomics and metatransciptomics may provide key insights into how soil microbial communities and root pathogens influence Armillaria root disease ...Missing: remote sensing LiDAR 2020s
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In search of a humongous fungus - CBS News
Feb 7, 2021 · Deep inside Malheur National Forest in Oregon is the world's largest living organism: a fungus, armillaria ostoyae, that spans thousands of ...
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Humongous Fungus - DK Books
In stockAug 17, 2021 · They affect other creatures, too, for example by helping break down food, or controlling their minds against their will.Missing: impact | Show results with:impact
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What the World's Largest Organism Reveals About Fires and Forests
May 21, 2022 · The Humongous Fungus is a symbol of an ailing, at-risk forest, unintended consequences of fire suppression, and the challenge of restoring an ecosystem's ...
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US Forest Service - Facebook
Apr 1, 2017 · It is a recently discovered clone of Armillaria ostoyae, the tree-killing fungus that causes Armillaria root disease. It may seem strange, but ...