Without winter there can be no spring; on the equator there are neither. Without seasons there is no change and life becomes a continuum; when it is always a nice day it is never a nice day. Contrast creates diversity and ultimately evolution. While the human spirit can be deadened by winter’s drabness, it is leavened by the first hint of abatement at the tail end of winter. Perhaps that is what Avon’s inimitable bard had in mind when he chose the title Winter’s Tale; a dichotomy of dark sadness and bright elation. The dialogue from Act 2 “A sad tale’s best for winter: I have one of sprites and goblins” establishes paradox. A sad tale for winter would not include sprites most noted for their whimsical fancy; Robin Goodfellow of A Midsummer’s Night Dream is well meaning if inept. The renowned essayist Samuel Johnson noted the contradictions essential to Shakespeare, who “has united the powers of exciting laughter and sorrow not only in one mind, but in one composition. Almost all his plays are divided between serious and ludicrous characters, and, in the successive evolutions of the design, sometimes produce seriousness and sorrow, and sometimes laughter and levity.”  In the first three acts of the Winter’s Tale, Sicilia’s king rampages in jealousy due to the imagined infidelity of his pregnant queen. With impetuous acrimony, he banishes the postpartum daughter to Bohemia as both the queen and his only son are smitten with grief and die. With an intercalary hiatus of sixteen years, the final two acts unite father and daughter in joyful reconciliation, the queen miraculously reincarnated from her memorial stone statue with Pygmalion flourish.  The rapturous, happy-ever-after climax is amplified by contrast to the dour prologue.
Hiking is a winter’s tale of Shakespearian contrasts. Stiff winter winds dig their icy fingers into any bare extremity while the frozen ground chills upward through layers of boots and socks. The rewarming that follows could never be as blissful absent the trial of the elements. Plodding ever upward against the insistent tug of gravity through despondent sloughs is the price of emerging at a prominence overlooking the journey’s path. Venturing on uneven tread requires navigation with full visual engagement and whole-body coordination of motor functions. There is little thought to this, a reflexive response; the cognitive mind is unburdened to promote a flow of new ideas. The body physic is unpinned and the mind is free to ponder unbound in the solace of nature. “The truths of the earth continually wait, they are not concealed either, they are calm, subtle, untransmissible by print, they are imbued through all things conveying themselves willingly, conveying a sentiment and invitation.”  Hiking is at the same time earthy and spiritual, contrasting yet entwined in harmony. While this is always so, it is most notable as a winter’s tale.
Winter scenery is reduced to starkness absent the leafy greens that await spring renewal. Annual plants expire and perennials strip to bare essentials of mostly hypogeal functions; the evergreens evolved to do both. Animals are out of sight burrowed in dens or arboreal cavities; insects survive as eggs the result of autumn copulations. Only the lichen and polypore fungi persist as hoary crusts and wizened brackets like the eyebrows of ents. Lichen fungi persist as if nothing has happened, employing their algal partners to provide sufficient nutrients from the diffuse light that remains. Winter is the domain of the polypores that slowly consume the cellulose and lignin of the fallen trees and of the lichens that set up shop on any convenient surface absent any need for roots or the water and nutrients that they carry. Winter survival requires self-sufficiency, a characteristic trait of recycling fungi. They are frequently named according to appearance: the British soldier lichen is adorned with the bright colors of red coats; the artist’s conk has a brown-staining surface that can be used as a canvas; and the turkey tail with circumferential bands looks like the tail feathers of its namesake, a true winter’s tale and tail.
A polypore is a fungus but not a mushroom. The distinguishing physiological feature of polypores is that they have many (poly in Greek) pores. A pore is a hole, which is in this case the opening of a long tube that extends upward and is the spore producing body of the fungus, akin to the gills of mushrooms.  According to the Linnaean system of biological suffixes, the approximately 2,000 species of polypores are in the order Polyporales and the family Polyporaceae. At one time they were mostly in the genus Polyporus now discombobulated into about 100 different generic groupings according to microscopic and biochemical details. Regardless, they are distinguishable by general appearance, most have a bracket attachment to the trunk or a branch of a tree that extends outward like a shelf; they are frequently called bracket or shelf fungi. However, some polypores grow out of the ground on a stalk and some are resupinate, a term that drives from supine or lying flat; they are called stalked polypores and crust polypores respectively. The polypore, whatever its shape and attachment, is only the fruiting body of the fungus, the spore producing agent of procreation. The actual fungus is embedded throughout the wood substrate and is comprised of branching, rootlike hyphae that intertwine to from the mycelium, the corpus of the fungus. The most important attribute of the polypore mycelium is the decomposition of cellulose and lignin, the two primary components of wood.
Cellulose is the most abundant polymer on earth and is produced at the rate of 1.5 trillion tons annually. Numbers of this magnitude can only be understood by analogy; an iceberg that broke free from Antarctica was estimated to have weighed in at one trillion tons, about the size of the state of Delaware.  Cellulose is one of the three primary components of plant cell walls; the other two are hemicellulose and lignin. The former is a misnomer of sorts, referring to all of the other complex sugars or polysaccharides that are not cellulose. Lignin provides stiffness and rigidity, essentially the glue that binds cellulose fibers together giving wood its strength. Sawdust is 40-50 percent cellulose, 20-30 percent lignin and 25-35 percent hemicellulose. The recycling of cellulose and lignin, sometimes called lignocellulosic materials, is mandatory for the restoration of carbon to the organic cycle that sustains life on earth. Fungi in general and polypores in particular are the primary agents for lignocellulose decomposition. Without them, earth would be inert, buried in dead tree trunks of sequestered carbon.  From a simplified ecological perspective, plants are producers, animals are consumers, and fungi are reducers. There is, as always, a downside; some polypores debilitate living trees as parasites and some infest man-made wooden structures resulting in serious economic depreciation and sometimes structural failure.
Polypores are divided into two groups according to decomposition results; brown rot fungi break down cellulose but not lignin and white rot fungi decompose both. This is accomplished by enzymes excreted by fungal hyphae that break down the complex molecular structures of wood into sugars and other compounds that are then used by the fungus as something like food; the most prominent are the aptly named cellulase and lignase. Brown rot is the more recognizable of the two; the dissolution of cellulose results in block-like wooden cubes that are uniformly light brown in hue due to high lignin content. Laetiporus sulphureus is one of the most common brown rot polypores. The common name Chicken-of-the-Woods is a matter of verisimilitude; when harvested young and properly cooked, it has the texture and appearance of chicken breast-meat. White rot is named for the bleaching effect on wood in consequence of cellulose, lignin, and even some hemicellulose degradation; Turkey tail or Trametes versicolor is a good example of a white rot polypore. It is not all that simple, though, as hybrids and exceptions are common. There are some white rot fungi that do not remove cellulose which are sometimes called white-pocket rots and some that are selective degraders according to local substrate conditions called mottle-rots.  Wood decomposition is just the beginning of the ashes to ashes and dust to dust of ecological turnover. The making of soil from the remnant hulks of fallen trees has a cast of thousands of millions.
Soil is a marriage of geology and biology. Ground up rocks imbued with organic detritus serves as repository for the elemental building blocks of living things. It is the realm of root and hyphal networks that cut through where legions of microbes live, love and die. Bacteria are the micro-decomposers that take over after the macro-decomposer fungi have taken the first whacks at cellulose and lignin. There are about a billion bacteria in every gram of soil, about one ton per acre or two cows worth.  Competition at the bottom end of the food chain is unrelenting and survival of the fittest is fast and furious. It is probable though not provable that plant cells originated when a bacterium with chlorophyll was consumed but not eaten by another bacterium and became a chloroplast; a similar scenario resulted in mitochondria, the power plant of all cells. Bacterial diversity can only be estimated at about one million different species, though some 2 percent comprise nearly 50 percent of soil communities worldwide  The two basic categories of soil bacteria are heterotrophic and autotrophic, the former needing external nutrients and the latter making their own; animals and fungi are heterotrophic and plants are autotrophic. The heterotrophic bacteria are the recyclers, breaking down the organic matter in the soil to the elemental level necessary for plant root accession. Soil bacteria and fungi are responsible for 90 percent of the carbon dioxide necessary in the atmosphere for plant respiration; one acre of soil is the exhalation equivalent of 50,000 people.  It takes a village to make a planet.
The sub rosa world of microbes might be characterized as a pitched battle between bacteria and fungi for control of enough turf for survival. It should come as no surprise that fungi that have evolved to overcome their bacterial nemeses could benefit humans, who are also subject to their relentless and ubiquitous onslaught. While many bacteria are good and some are essential, there are a few bad actors. In 1928, a Scottish physician and microbiologist named Alexander Fleming was conducting experiments with pathogenic staphylococcus bacteria grown in pure culture. What happened next has endured as the quintessential example of serendipity in science and the unkempt laboratory; one of his samples left unattended for some time had become contaminated with mold. Whereas most would wash up and move on, Fleming’s trained eye fell on the ring of apparently dead bacteria that surrounded the mold. With the perspicacity of Prometheus, he identified the mold as the fungus Penicillium notatum and named the excretion penicillin. He published his results without fanfare in a British scientific journal, its potential as miracle drug unrealized. The gathering storm of World War II and its attendant carnage galvanized the broader scientific establishment to antibiotic action. With the “overcome all odds” overdrive of a mini-Manhattan Project, the Rockefeller Foundation funded the engineering development of fermentation and extraction of penicillin in large quantities. In 1942, Anne Miller was dying of a bacterial infection in New Haven, Connecticut when her doctors obtained enough of the newly developed antibiotic to try on her as a last resort; she lived another 57 years and died at the age of 99. Untold millions have since been saved by the fungal medicine; Fleming won the Nobel Prize in Medicine in 1945 just as the war ended. 
There is nothing particularly modern about using fungi for medicinal purposes, Asian practitioners have been using them for millennia and there is strong evidence of use by Neolithic hunter-gatherer populations. While we have all now become inured to drugs in plastic containers with a sometimes-removable child-proof caps, before Lavoisier, there was no chemistry per se and drugs were discovered in nature by trial and error; this is now considered herbal medicine. Some of these primordial drugs worked well, some were probably helpful but could be improved upon with modern formulation and some were certainly placebos effective only with appropriate shamanistic exhortation. Medicinal polypore fungi seem to fall into the first category as scientific evaluations of their attributes has in general demonstrated efficacy. Fungi are found to be most useful in broad categories such as stimulation of the immune system, anti-viral, and anti-tumor with an ultimate result of enhanced wellness and longevity. While this may sound Panglossian, there is a reasonable hypothesis that provides some rationale for verity. Biologists assert that fungi are physiologically closer to animals than plants. They therefore have had to deal with similar microbial, existential threats against their well-being. Fungi are highly evolved chemical factories that evolved to produce exotic enzymes to break down molecules into usable nutritional quanta. It is not implausible that they evolved equally potent compounds to hold the dogs of microbial war at bay. This could rise to probable as, after all, why else would they have survived? 
Turkey Tail is likely the most well documented of all the fungi from the standpoint of medicinal applications. Known as Yung zhi in China and Karawatake in Japan; most of the research on its effects has been conducted in Asia where it is widely prescribed. Turkey Tail has notable and measurable effects on tumorous carcinogenic growths with some organoleptic specificity. The trials have included in vitro (outside the body in an artificial environment), in vivo (live animal) and human clinical evaluations. The non-human trials have demonstrated that the chemical components extracted from the Turkey Tail have potential in adjuvant cancer therapy, which is to say that they enhance the effect of other drugs in shrinking tumors when taken in concert with the primary drug.  This ameliorative effect is also referred to as a biological response modifier, or BRM; the additive component (in this case a derivative of the fungus) acts as a modulator of the immune system in improving the host body’s tumor response. As an example, a meta-analysis of eight separate controlled and randomized trials which included 8,009 patients that was conducted in Kyoto, Japan in 2007 revealed that the use of adjuvant therapy with extracts from Turkey Tail fungi “improves the survival of patients after curative gastric cancer resection.”  Other trials have demonstrated similar statistically significant effects on prostate, esophageal, colorectal, breast and lung cancers. 
The compounds that are extracted from Turkey Tail are polysaccharides, long carbohydrate molecules that break down when hydrolyzed into monosaccharides like glucose. Polysaccharide kureha, simplified to PSK, is the predominant fungal compound used for medicinal applications; it is sold commercially as Krestin. PSK has been an approved cancer drug in Japan since 1977 where annual sales are estimated at over half a billion dollars, about 25 percent of the total Japanese expenditure for cancer-related drugs. A second polysaccharide that has more recently been extracted from Turkey Tail is polysaccharide peptide, or PSP. It differs chemically from PSK in its constituent monosaccharides; PSK yields rhamnose and arbinose and PSP yields fucose. The more important functional difference, however, is in the modulating effect of PSP on the immune system; trials have indicated potential as an agent against HIV replication. The enzymatic efficacy of Turkey Tail also makes it a strong candidate for mycorestoration, the use of fungi to remove harmful materials from the environment. This has been demonstrated in numerous studies of a variety of contaminants including organophosphates and mercury. As a white rot fungus, which means that it can decompose both wood cellulose and lignin, it has great potential for other industrial processes, notably the bleaching of wood pulp. 
1. Johnson, S. “Preface to Shakespeare”, Prefaces and Prologues to Famous Books, The Harvard Classics, C. Eliot ed. Collier and Sons New York 1909 Volume 39 p. 213.
2. In Greek mythology, the sculptor Pygmalion created a statue so beautiful that he became enraptured of it. Aphrodite brought the statue to life as Galatea in recognition of his ardent amour. George Bernard Shaw wrote the play Pygmalion about a flower girl transformed in manners to a lady. My Fair Lady is the cinematic, musical version.
3. Whitman, W. Leaves of Grass, “A Song of Rolling Earth” The Easton Press, Norwalk, Connecticut, 1977, p 204.
4. There is also a group of mushroom-shaped fungi called boletes that have tubes with pores. The tubes are short-lived and can be peeled away from the cap, as is the case with gills on other mushrooms (but not polypores)
5. Mooney, C. “One of the biggest icebergs in recorded history just broke loose from Antarctica” Washington Post 12 July 2017.
6. Eida, M. et al “Isolation and Characterization of Cellulose-decomposing Bacteria Inhabiting Sawdust and Coffee Residue Composts” Microbes and Environments, September 2012, pp 226-233.
7. Blanchette, R. Wood Decay: The Action Behind the Polypores, Fungi Volume 11 No. 4, Fall 2018, pp 10-19.
8. https://www.nrcs.usda.gov/wps/portal/nrcs/detailfull/soils/health/biology/?cid=nrcs142p2_053862 The USDA uses two cows for weight at 500 pounds each
9. Delgado-Baquerizo, M. “A global atlas of the dominant bacteria found in soil” Science volume 359, 19 January 2018, pp 320-325
10. Nardi, J. Life in the Soil, Chicago University Press, Chicago, 2007, pp 1-8.
11. Kendrick, B. The Fifth Kingdom, 3rd Edition, Mycologue Publications, Newburyport, Massachusetts, USA, 2000. pp 334-340.
12. Stamets, P. Mycomedicinals An Informational Treatment on Mushrooms. MycoMedia Productions, a Division of Fungi Perfecti, LLC, Olympia, Washington, 2002 pp 5-17.
13. Jimenez-Medina, E. et al “The immunomodulator PSK induces in vitro cytogenic activity in tumour cell lines via arrest of cell cycle and induction of apoptosis” BMC Cancer 2008 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2291471/?tool=pmcentrez
14. Oba, K. et al “Efficacy of adjuvant immunochemotherapy with polysaccharide K for patients with curative resections of gastric cancer” Cancer Immunology, 2007 at https://www.ncbi.nlm.nih.gov/pubmed/17106715
15. Kobayashi, H. et al “Antimetastatic effects of PSK (Krestin), a protein-bound polysaccharide obtained from basidiomycetes; an overview” Cancer Epidemiological Biomarkers, 1995 at https://www.ncbi.nlm.nih.gov/pubmed/7606203
16. Stamets, P. Op. cit. pp 42-44.