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Of Fungus and Falcons

Abby Duvall, a student in my 2010 class Medical and Veterinary Mycology wrote this post. She volunteers with the Cornell Raptor Program, and knows a lot about these beautiful birds.

The young falcon, taken from a wild nest, had the best of care. She dined only on the finest of quail, had immaculate housing, and was treated like royalty. When she reached the age of four months she began her training as a falconry bird. She progressed quickly, learning to come to a swinging lure and take a high pitch. Suddenly, the beautiful bird began to lose weight, with a weight drop of 20% in only 5 days. She became lethargic and began to have trouble breathing. Soon she stopped eating altogether. The antifungals that had been prescribed had little effect to reverse her decline. She died the next afternoon, felled by the fungus growing inside her. Such is the face of avian aspergillosis, the stealthy killer.

The unlikely pairing of fungus and falconry has ancient roots. The “Sport of Kings,” falconry has long been plagued by the lethal fungal disease aspergillosis. Since the early 1800s we have known of this disease in wild birds, and it was probably the reason for the historical difficulty in obtaining and keeping the elegant white gyrfalcons of royalty.¹ In raptors, Aspergillus fumigatus is the culprit in 95% of cases.² Unfortunately, this fungus is a relatively common environmental contaminant because of its usual role as a saprobic decomposer². In any given year, a large percentage of wild hawks may test positive for Aspergillus spores in a throat swab¹, but few will develop disease. Some species of raptors are more susceptible than others, with goshawks, gyrfalcons and redtailed hawks having a high risk of infection.

Aspergillus fumigatus is an opportunistic fungus. It does not usually cause disease in a healthy hawk. However, hawks which are at a low weight, injured or sick are all under stress, decreasing their resistance to infection. Young first-year raptors are naturally under a lot of stress as they attempt to survive their first winter, with up to 80% mortality. The young raptors appear to be most prone to infection around 2 to 4 months of age.² Unfortunately, this is exactly the age at which most raptors begin their training for falconry, resulting in this fungus’ status as the most common and most lethal disease of captive birds of prey.⁴

Young birds used in falconry face relatively few threats from predators, injury or illness compared to their wild cousins. Most are kept only one year and are then released to contribute to the wild breeding populations. The problem is that keeping raptors in captivity creates a few challenges in housing in order to prevent aspergillosis. Perhaps one of the most important aspects of prevention is proper housing design.

A captive hawk’s home is called a mews. Generally this is a building with both an inside and outside portion and many perches — there are countless variations. A large part of the problem with aspergillosis in falconry birds used to be caused by the substrate placed in their housing. In conditions which are either too moist or too dry and dusty, high levels of spores can be carried into the air. Problematic substrates include sand, sawdust and peat, all of which do not drain well when wet and can become dusty when dry.³ Today most raptors are kept on pea gravel or other well-drained surfaces to prevent Aspergillus growth. In addition, buildings are designed with airflow and hygiene in mind in order to prevent the buildup of mutes, or feces, and stale air.

Raptors most often develop one of two different forms of aspergillosis. In the acute form, a bird inhales overwhelming doses of spores from a single source, which rapidly results in large numbers of granulomas, or inflammatory tumors, in the lung.³ Affected birds usually die within a week, although cases of less than 48 hours have been recorded! The other form can be far more insidious, in that affected birds may not show obvious symptoms of infection in early stages. Gradually, large granulomas form in the lungs while furry mats of sporulating mold develop in the air sacs and airways. Despite sporulation inside the live bird, no direct transmission has been recorded.³ Some unusual, chronic cutaneous and ophthalmic (eye) forms are also found in raptors. The chronic forms can be treated if caught in time, but treatment is very difficult and misdiagnosis is common.⁴

The best treatment for aspergillosis in infected birds is generally through high doses of antifungal drugs: azoles or amphotericin B.³ Generally birds with acute infections never recover, while those harboring chronic infections must be carefully monitored to make sure that the infection is fully cleared before discontinuing drug treatment. In any diagnosis of aspergillosis in a raptor, prognosis is guarded due to the number of pneumatic bones. These are hollow and connect with the respiratory system, providing deep loci for Aspergillus invasion, while at the same time sheltering the fungus from antifungal drugs.

Due to the difficulty in treating aspergillosis, falconers have now turned to preventative medicine in new birds. Treatment usually lasts for two weeks with oral itraconazole or nebulized clotrimazole.^2,3 The potential problem with preventative treatment is the possibility of fungal resistance if the bird already had a low-grade chronic Aspergillus infection which was not cleared in two weeks. Some falconers have begun to hybridize more susceptible raptor species with much hardier species.² The fully imprinted, captive-bred offspring ideally have the disease resistance of one parent combined with the size or strength of the other parent, as is seen in the many gyrfalcon hybrids.

While there are ways to preventatively treat for aspergillosis today, this disease still claims the lives of many raptors each year. It can suddenly overtake a bird in perfect health with alarming rapidity, or slowly eat away at the lungs of a young falcon with hardly a sign of the disease externally.

A fungus walks into a singles bar

Kathie Hodge wrote this with help from Bradford Condon, initially in response to Clear’s question about sexual reproduction in fungi. But perhaps you’re all wondering. Ready?

During a radio interview once the host asked me to explain fungal sexuality. My answer was a bit too intricate and long to make it into the broadcast–I got bogged down in the details. It’s not that you need a PhD to understand how fungi have sex, it’s just that it’s a most unfamiliar kind of system, in which analogies to human sexuality will get you in trouble. People occasionally ask me about this, and I’ve really never come up with a solid, succinct answer. So I thought I’d have a try at a kind of introduction to the sex life of fungi–at least the part that has to do with sexual compatibility. You tell me what’s unclear, and maybe we can collaboratively improve this piece.

My gift to you: 2.5 days worth of emergence by the dog stinkhorn, Mutinus caninus. It is here mainly to provide an outlet for your anthropomorphizing. The spores of this stinkhorn are its sexual offspring. They are produced in the stinky green goop on the head of the thing. Further words elude me, but for more stinkhorn sauciness, have a look at Michael Kuo’s Stinkhorn Hall of Fame and our own other stinkhorn posts. Time lapse video by Kent Loeffler.

The trickiest concept for discussing fungal sex is “gender.” In humans, there are men and there are women (from a strictly reproductive point of view), and it takes one of each to make a baby. The male donates some genetic material (a gamete, the sperm), which is received by a female gamete (the egg), and those gametes get together to form a new human. We trust you’re all familiar with this scene.

Among fungi, any individual can donate or receive genetic material–so you can already see we need to let go of the concept of gender. Let’s talk instead in terms of what mycologists call mating types. A fungus simply needs to find a mate of a different mating type. Of the fungi you might be familiar with, hmm, most species have only two mating types (they’re bipolar), and some have four or more possible mating types (they’re tetrapolar). Any particular individual of a species is just one mating type, of course. Most molds have two; many mushrooms and bracket fungi have four or more. A few fungi, like the unassuming split gill, Schizophyllum commune, have more than ten thousand!

In the same way that our genders are controlled by our genetics (Kathie has two X chromosomes; Bradford has an X and a Y), mushroom mating types are determined by genes. In mushrooms, either one or two sets of genes control the ability to mate. Mating type genes in fungi don’t confer secondary sexual traits like facial hair or Adam’s apples; they do control 500 to 1000 genes involved in the development of sexual structures and spores. Shockingly, either fungus partner can get pregnant (by making a mushroom), or be a dad (by delivering a gamete), or both. The whole division of labor thing is an animal quirk.

Now here is where it gets really crazy. If you haven’t shed your attachment to gender, now’s the time. In many large, charismatic fungi, genes at two different locations on the chromosomes control what’s called a tetrapolar mating system. In these fungi, two individuals must differ at both loci to make a good match. Now let’s say you’re one of these fungi. If at location MAT-A you have the A2 mating type allele, and at location MAT-B you have the B1 mating type allele, then your mating type is A2B1. You must find a partner who is different than you at both locations (may I suggest A1B2?). Your beautiful baby spores will be this mix: A1B1; A2B2; A1B2; and A2B1. If your babies should get together and try to mate (perish the thought), they will only succeed 25% of the time. Hello? You with me?

It got a little complex there, didn’t it? The deal is, a fungus just has to find a mate of a different mating type. So actually, when a species has a lot of mating types, it’s EASIER for an individual to find a mate, because the odds go up. In contrast to humans–a human can typically mate successfully (have kids, I mean) with about half the people in the room. But a fungus might find that nearly everybody on the dance floor is a potential mate. See?

Homosexual fungi? Well, not exactly. At least in the human version of homosexuality nobody’s going to get pregnant without some outside input. But there are some fungi that are self-compatible (homothallic)–they can have offspring without a partner. There are two ways to do this. One is to have copies of all the needed mating type alleles in each nucleus (in the majority of mushrooms, a spore contains only a single nucleus, and a haploid one at that). The other way to go is to pack two different, compatible nuclei into a spore, ready to mate. This latter method is how the common supermarket button mushroom does it. I know! It seems like such an ordinary mushroom.

The other kink of fungi (best friends forever?) is that even if they are not sexually compatible (because they are of the same mating type), different individuals of a species may be vegetatively compatible. An entirely different genetic compatibility system dictates whether they can fuse their mycelia to share resources, even though they’ll never have sex. Intriguingly, there are no sexually transmitted diseases among fungi, but there are myco-viruses that can be spread through vegetative compatibility. I’m sure there’s a “nonsexual STD” joke trapped inside this paragraph…

It’s all horribly interesting. There’s much more to say. But it is hard to get our minds around some of this stuff, just because we’re so used to the silly but familiar animal model.

p.s. Were you really expecting me to tell the joke? I’m not telling the joke.

Ringworm in Cats: Percy’s Case

We cover all kinds of fungi here on the Cornell Mushroom Blog. This post on fungi that would like to eat your cat was written by Stacey Burdick, a smart, cat-loving student in my class, Medical and Veterinary Mycology.

My cat Percy turned 16 this March. For almost his entire life, he was a healthy, hardy, active cat; but everything changed in the spring of 2007. That spring was the start of a series of bacterial and fungal infections that led me to my topic: Ringworm in cats. Ringworm is a skin disease caused by any of a handful of different fungi that grow on the surface of the skin, causing irritation. To fully explain my cat’s case, I have to start with a previous infection.

During spring break of my sophomore year at Cornell, I came home and noticed that one of Percy’s toes on his left front foot was hairless and swollen. My mom took him to the vet, who explained that it was most likely just irritation that would go away. When I came home from school in May, it had not gotten any better; in fact, Percy’s entire left front foot was hairless and very pink. We took him back to the vet, and this time he performed a culture that came back with positive results for a notorious bacterium: MRSA, methicillin-resistant Staphylococcus aureus. Percy was instantly put on antibiotics, which he took until the spring of 2008. At that point, Percy’s hair was growing back and we performed another culture that confirmed he was no longer infected…all-clear, right? Wrong.

The following summer, Percy started losing fur again, except this time it spread about a third of the way up his left front leg and onto his face and right front leg. We took him to the vet frequently but were at a loss as to what could be causing it. Percy was also scratching his head a lot. The vet was scratching his head too, and said it probably wasn’t a fungus like ringworm because cats don’t normally get those infections unless they have depressed immune systems. By fall, we still didn’t know what was wrong with our cat even after taking him to another veterinarian, but my family was experiencing fungal infections of our own. Each member of my immediate family was treated for ringworm, and I had an infection on my elbow that a nurse at Cornell’s Gannett Health Services said was the “biggest she had ever seen.” Ringworm in people can be acquired from animals, and a cluster of cases in a family implicates a common source like the family pet. So when I was home for fall break, my mother and I took Percy to the second vet again and asked if, against all odds, it could actually be ringworm. He didn’t think so, because it didn’t present normally–no red, raised, or circular lesions, and when he looked at Percy’s face under a Wood’s lamp it did not fluoresce.** However, the vet pulled some hairs from Percy’s face and sent them to a laboratory who would see if anything could be grown from them.

About a week later, we received a call from the vet, who told us Percy did indeed have ringworm, and that the fungus Microsporum canis was the culprit. He also recommended we run tests for feline AIDS (FIV) and feline leukemia virus (FeLV) to see if one was the underlying cause of immune depression leading to Percy’s fungal infection. The tests came back positive for FIV, and in the meantime Percy started treatment with itraconazole, an antifungal drug. The vet wasn’t optimistic about Percy’s chances of recovery, but after a few months of oral medicine and medicated Sebolux baths Percy started to regrow hair, stopped itching, and his skin looked much less dry. We thought, once again, that we were out of the tunnel.

We thought too soon. In spring, Percy started losing fur again, this time worse than before. We kept shampooing him but it wasn’t helping, so we brought him back to the vet. This time, the culture revealed a different agent of ringworm–a species of the fungus Trichophyton. Percy’s prescription was changed to oral fluconazole, a different antifungal drug, and within about 6 months Percy’s hair had grown back again. One final culture came back negative for the various fungi that cause ringworm, so Percy was finally free of his infections.

The second vet we took Percy to was fascinated by his case. He talked to veterinary dermatologist colleagues about it, to get their opinions and compare notes. Ringworm is common in shelter cats, as the causative fungi can spread very easily among cats,⁴ but it is less common for an individual cat in a house to become infected. As I said before, cats have natural immunity when they are healthy, but kittens less than one year of age¹ and immune-depressed cats are at risk. Cats self-clean, and this practice may remove fungal spores, assisting in immunity to fungal infections.⁶ Ringworm is three times more likely to occur in FIV-positive cats, who are more susceptible to a number of diseases. A cell-mediated response is necessary for recovery from ringworm,⁵ but FIV affects the T-cells of the cat’s immune system,³ allowing FIV-positive cats to become easily infected and making recovery very hard. Vaccines have been produced for cattle and there is a commercial vaccine for cats as well, but its availability is limited⁵ and more research is needed.² Another interesting fact that my family experienced is that cats are the main source of human infections¹ and that at least one person in 70% of households with an infected cat will experience ringworm infections of their own.⁵

While Percy was at risk for ringworm because of his FIV, thankfully he has now recovered from his infections. He may never fully regrow hair on his ears (they’re covered with peach fuzz now) and he won’t be winning any beauty contests, but at least he is relatively healthy again. I wanted to share this experience and some of the knowledge I have gained as a result.

Tree slime, stump flux and microbial consortia

That fine FAM fellow is back, this time nosing around after some seeping stumps.

At this time of year, please watch where you are going in the woods. Strange fluids are oozing, such as this orange paste, seeping from cut hardwood tree trunks, where gnomes with chainsaws were once busy. Get this stuff on your fur, and no one will know what to think.

Root sap gets stirring in the Spring, and even if the stems are gone, the roots may still be alive and pumping liquids, unaware there is no top to feed. Any self-respecting microorganism knows a free meal when it sees one, and soon the watery slime is translucent and greasy with yeast and bacterial and filamentous fungal growth.

My own tree slime is actually relatively modest. Have look at the stumpy volcanos below, photographed last Spring by Jackie Donnelly, one of this Blog’s readers.

Here are some of the budding yeast cells from my tree as seen with the microscope. Orange storage bodies fill up much of each cell. There are lots and lots of yeasts, and most are very talented at growing in watery places with lots of sugar. Then they bud and bud and bud and make their pigments and all their extracellular polysaccharides and make everything nice and mucusy.

Everybody knows about yeasts from the immortal words of Yeats:

Yeast make bread

Yeast make wine

Yeast make you happy

All the time¹

Most yeasts are not Saccharomyces, so what species are in this particular slime? In the old days, yeast identification was the work of mad scientists with many suspicious stains on their lab coats. Fifty or sixty different media were needed, each with a unique carbon or nitrogen source. The mad scientist would stab the yeasts into test tubes full of semi-solid gelatin, being careful not to singe their fingers in their bunsen burners. Then they would hold the tubes up to the light, waiting for gas to bubble up from the dividing yeasts into smaller tubes put upsidedown in the bigger tubes, or for dyes in the media to change colours following the release of organic acids. It was an exciting time, but a productive yeast identifier was lucky to identify a dozen yeasts per week.

Nowadays, yeast identification is an entirely modern affair involving singing and dancing and lots of enzymes and machinery. A productive yeast identifier with well developed pipetting muscles can handle hundreds of yeasts per week. Fortunately, I have Molecule Man, and although he only knows four letters of the alphabet, he can extract very long and unique (unpronounceable) words from any living thing. With a culture of our slime yeast, he did his tricks.

Our little yeast is called Cryptococcus macerans², a basidiomycete yeast first discovered in Denmark, mostly found in sweet wild fluids in frigid parts of the globe such as Iceland and Patagonia and now from wherever it is I live. The orange pigment is of course carotene, the same chemical that colours carrots, and probably my fur. This is one of a group of yeasts that really don’t like each other yeasts very much. They slaughter each other with killer toxins called mycocins.

There are other species in this slime, including moulds like Fusarium and that musical-sounding Acremonium. Actually, a few fungi have only ever been found on cut stumps. Collecting specimens takes great persistence; a Swiss Army Knife will not do. A chisel and a hammer are the usual tools, but despite how careful you are, valuable bits of fungus go flying off into the debris like wayward potato chips. If you try to collect from trunk ends yourself, please wear protective goggles. Some strains of Cryptococcus macerans have actually reportedly been isolated from diseased humans. I’m only a dog, but I do rely on humans to throw Frisbees and I can’t afford to lose you.

If you want to explore this subject further, the May 2006 issue of The Mycologist includes an article about a ‘microbial consortium’ on birch stumps in Germany, with additional lurid photographs of trunk slime that put the most colourful stalagmites to shame. This article, and the followup review of Russian tree slime, will lead you into the deep exotic science of these exudates and some of the species that can be found there.

This bark glows in the dark! Bioluminescence in mushrooms

My talented student Emily Isaacs wrote this post. She bravely took both my outdoorsy Mushrooms class and my creepy class in Medical and Veterinary Mycology.

It’s the 21st Century and ‘glow-in-the-dark’ is all the rage. We put plastic stars on our ceilings that shine in the night to mimic the constellations and we insert genes into our zebrafish to make them glisten in their tanks. From nail polish and glow sticks to now even puppies, we’re fascinated by our ability to manipulate objects otherwise unseen in the dark. But long before we artificially created glow-in-the-dark objects, a few fungi evolved to use this characteristic we so desire.

The phenomenon in nature is called bioluminescence and is restricted to a small group of species. While most fungi don’t possess this ability, there are some 71 known species of bioluminescent mushrooms contained within three groups— the Omphalotus, Armillaria, and Mycenoid lineages. Their degrees of light intensity differ; while many of the Australian species are very luminous, North American species tend to emit less light and require adjustment to the dark before they can be seen.² Reports of these fungi date back to Pliny the Elder in the first century, who described luminescent white wood-decaying mushrooms in France. Even earlier, Aristotle had commented on glowing rotten wood, now known to be a product of the luminescent mycelium within, a subject which continued to be one of great mystery throughout European history^2,4. In 1555, Swede Olaus Magnus published A Compendious History of the Goths, Swedes, and Vandals and Other Northern Nations, which mentioned numerous luminescent mushrooms such as the “Agarick” and their connection to wood decay; he also described the practical use of mycelia-infested bark (often called “Foxfire” or “Faerie fire”) by Scandinavians during long winter nights. The practical uses of these mushrooms extended to other areas of the globe as well; in the late 17th Century in Herbarium Amboiense, Dutch physician G.E. Rumph commented on how Indonesian natives used bioluminescent mushrooms as primitive flashlights. And even in 20th Century Micronesia, these special mushrooms were incorporated into ritual headdresses and warfare face paint.⁴

Various other organisms also bioluminesce. Many people are most familiar with the firefly, which emits flashes of light produced by the pigment oxyluciferin. Numerous studies have revealed their flickers act as a form of communication between individuals and are vital in the selection of mates. Firefly larvae similarly glow–perhaps in order to advertise their unpalatability and so discourage predation.^1,5 The femme fatale Photurus firefly is a particular case— she uses her light to attract and consume eager male fireflies of other species.¹ Another fluorescent insect is the fungus gnat (whose light abilities are unrelated to the mushrooms in which they reside). These flies bioluminesce primarily to attract prey to their webs, although other uses include deterring predators, displaying larval strength to neighboring aggressive larvae, and locating mates.⁷ A handful of marine animals incorporate symbiosis with fluorescent bacteria into their predatory behavior. Deep sea flashlight fish and female anglerfish use this light to attract prey in the dark depths of the oceans.³ Cookiecutter sharks use their luminescent undersides in the opposite manner; the emitted blue-green camouflages with the surrounding ocean so only a small black patch is visible. Other predatory fish, such as tuna, perceive the shark to be much smaller than it really is, and when these other fish approach their ‘prey’, the shark attacks (and subsequently consumes) its predator⁸.

In comparison, bioluminescence in mushrooms is often assumed to play roles in spore dispersal and increased survival. Unlike some marine species, fluorescence in mushrooms is produced without endosymbionts. One fundamental effect of mushrooms’ light, as shown by Sivinskif, is its ability to more successfully lure arthropods, in particular Collembola and Diptera. These bugs may aid in spore dispersal, much as the stench of stinkhorns does. Appealing to arthropods at night could give bioluminescent mushrooms an additional half day advantage over their non-luminescent counterparts, assuming insects would eat or pick up the spores and then drop them elsewhere. Alternatively, perhaps the mushrooms are unsavory to insects and luminescence emphasizes their toxicity at night. Illumination may also discourage negatively phototropic fungivores, especially those found in the soil (hence one explanation for why the mycelia of these species also glow). Luminescence might also attract carnivores to eat arthropods on the mushrooms, with the assumption that if more carnivores than insects are attracted, then predators of the fungus are limited overall.^6,7 But not all hypotheses are centered around the relationships of the fungus with other organisms. All known glowing mushrooms are wood decayers that can digest lignin, a particularly big and difficult molecule that helps bind the cellulose fibers of wood together. An alternative idea is that bioluminescence is a side-product of lignin degradation: Reactions that lead to light production may generate antioxidants to protect the fungus from toxic peroxides released during lignin digestion.²

The next time you step out in the woods at night, leave your flashlight home–if you look closely enough, you may find yourself face-to-face with one of these fascinating bioluminescent mushrooms.

Agarikon

This post was written by an intrepid student in my 2009 class, Mushrooms of Field and Forest (PLPA 3190)

Long before the Pacific Northwest region of North America was associated with coffee-drinkers and lumberjacks, the Indigenous Peoples of the Northwest Coast, including the Tlingit, Haida, Tsimshian and others, were the sole inhabitants of region. Spiritual life, the supernatural, and a respect for the environment and its resources were integral parts of daily life for these Indigenous Peoples of the region. In particular, one large tree-dwelling mushroom, Fomitopsis officinalis, was revered for its medicinal and spiritual properties. This species was tool of the local healer and spiritual figure in the communities, the Shaman. When a Shaman died, Fomitopsis officinalis, in various carved forms and figures, were placed at the head of the grave to act as guardians, protecting the shaman during his “long death sleep” (1).

Fomitopsis officinalis (=Laricifomes officinalis) is a hefty, bracket fungus and can be found on the trunks of coniferous hosts, where it causes a brown-rot (3). The fruiting bodies persist for many years, becoming longer and longer as they grow. This species occurs worldwide, and has gone by several common names including Agarikon, Quinine Conk, Larch Bracket Mushroom, Brown Trunk Rot and Eburiko. The large sporophores were documented over 2000 years ago by the Greek pharmacist Dioscorides, who recorded the mushroom’s effectiveness in treating Consumption, which we now know as Tuberculosis. Throughout the ages, early Europeans and Central Asians traditionally used this species for treatment of many ailments and infectious diseases, including coughing illnesses, asthma, rheumatoid arthritis, bleeding, and infected wounds (2). The key pharmaceutically-active compound found in Fomitopsis officinalis is Agaricin (or agaric acid), a white, water-soluble powder that can be administered both orally and topically. Agaricin is an anhidrotic, anti-inflammatory, and parasympatholytic agent, and is now produced synthetically by many pharmaceutical companies (5).

Interestingly, the medicinal properties of Fomitopsis officinalis are believed to have been discovered independently by the isolated Indigenous People of North America. In North America, these fungi were referred to as “bread of ghosts” or “tree biscuits,” references to the spiritual powers of the mushroom and its hanging fruiting bodies. The mushroom was an important resource for Shamans, who would apply Fomitopsis officinalis powder to cure ailments thought to be caused by supernatural forces.

These fungi were not only utilized for their medicinal properties, but were also valued as spiritual and supernatural objects. The large fruiting body structures were often carved to represent various spiritual figures and spirit catchers, as assumed by the large orifices in the mouth and stomach. These carved figures were often hung from the ceiling of special dance houses of the Shaman to protect the people during rituals. Because of the key role Fomitopsis officinalis played in the life of the Shaman, it was only natural that the mystical fungi should accompany him in the afterlife. The sporophores were carved as jewelry, painted or sometimes coated in a protective substance and placed at the head of the shaman’s grave site, to serve as his “grave guardians”. These grave guardians not only protected the shaman’s burial site, but also warned people of the area that the site was occupied by spirits and should never be approached (1,4).

Many of these grave guardian artifacts, collected by explorers and archeologists in the late nineteenth century, were originally believed to be made of wood. It was only recently, when investigating wood deterioration in these “wooden” artifacts, scientists realized the grave guardians were in fact a fungus. Fruiting bodies of F. officinalis are perennial: Each year (or so) a new layer of spore-producing tubes grows at the bottom of the conk. In the past, these the tube layers had apparently been mistaken for the annual growth rings of a tree. Microscopic examination of the hymenial layers revealed the fungal origins of the grave guardians (1). These artifacts can now be found in the collections of several North American museums. As for the great Fomitopsis officinalis, although once common throughout most temperate regions of the world, it is now believed extinct in most of Europe and Asia. However, it can still be found deep within the old-growth forests of Washington, Oregon and British Columbia in the Pacific Northwest, and modern-day mycophiles continue to stress the importance of this valuable and historic polypore.

Watch a 2008 Agarikon hunt with Paul Stamets (Founder and President of Fungi Perfecti), filmed by Bill Weaver:

Note: For more information, including wonderful pictures of the grave guardian artifacts (not reproduced here for copyright reasons) please consult the work of Blanchette et al. 1992 and their paper entitled, “Nineteenth century shaman grave guardians are carved Fomitopsis officinalis sporophores”, found in the journal Mycologia.

Mushrooms as Sacred Objects in North America

A delightfully radiant and muddy-toed student in my Mushrooms of Field and Forest class wrote this essay, and illustrated it too.

Ethnomycology! What a mouthful. Ethnomycology is the study of how people have used fungi – as food, tinder, medicine, and spiritual tool – and how this use has influenced them. Many cultures of the world consider mushrooms to be sacred curers of sickness and givers of information. You’ve probably heard of the Amanita muscaria, that handsome red mushroom with white spots, or maybe even of the Psilocybe mushrooms of Mexico, so sacred they were called “God’s Flesh.” An intriguing but less discussed topic is the use of fungi by Native Americans of North America.

Haploporus odorus is found above 52 degrees latitude in Canada and Northwestern Europe. It is a polypore – a stalkless shelf-like fungus with pores on its undersurface. It is white, hoof-shaped, and grows on willow trees in conifer forests. Upon close observation one can easily notice the unique characteristic of H. odorus – its smell. The fruiting bodies have a strong odor of anise, kind of like licorice. This smell is strong and persistent, and dried specimens retain their odor. Native Americans appreciated the smells of plants like sage and sweet grass and used these plants for purification rituals. Because of its strong fragrance and other medicinal properties, Haploporus odorus has been an important fungus in the culture of Northern Plains Indians.

Indians used H. odorus as a spiritual symbol, a decoration of sacred objects and a healing tool. The fungus was used to stop wounds from bleeding, made into an infusion to treat diarrhea and dysentery, and combined with another fungus in an infusion to treat coughs. It was burned to produce healing perfumed smoke, and some elders wore necklaces of pieces of the fungus strung on a leather thong as protection against becoming ill. Indians took this fungus from the willow tree, carved it into smooth ovals, and then decorated them with burnt line patterns. Some pieces of fungus were strung onto leather thongs to create necklaces–have a look at this Alberta Plains necklace and ermine ornament courtesy of the Canadian Museum of Civilization. Other pieces were used to create medicine bundles – powerful collections of sacred objects. So revered was this fungus that the Native Americans even used it as an adornment on sacred war robes and scalp necklaces. It’s clear that it was associated with protection and power.

Another interesting fungus (though not so sacred) is Phellinus igniarius. This polypore grows on birch trees in the interior of northern North America. Native American use of this fungus has been recorded since the 19th century. Coastal Alaskan peoples traded with the Yukon Indians of the interior to obtain it. The Yupik and Dena peoples of the far northwest kept the ashes of P. igniarius in small, beautifully decorated boxes. The boxes were made of ivory, wood, or bone, and then decorated with materials like strips of antler, polished walrus teeth, and tufts of seal hair. You’re probably wondering, ‘Why in the world would anyone keep fungus ashes in beautiful boxes?’ Phellinus igniarius was, and still is today, widely used by the Yupik of Alaska as a masticatory and for smoking purposes. Before tobacco was introduced by the Europeans, the Yupik mixed the burnt fungus ashes with other plant materials, such as cottonwood bark, and smoked or made a quid out of this mixture. Later, they mixed the ashes with tobacco to give it a “powerful kick.” Today, the ash-tobacco mixture is sold in native Alaskan communities under the name iqmik. Please read more about iqmik in this fine essay by Diane Pleninger and Tom Volk, and see a slideshow on iqmik and its dangerous impacts courtesy of Alaska Magazine. It turns out that the alkaline chemicals in the fungus enhance the absorption of nicotine. It’s no wonder that one Indian name for Phellinus igniarius is “elch’ix”, which translates as “burning taste.”

Perhaps the most intriguing use of fungi in North America is the Northwest Coast tribes’ use of Fomitopsis officinalis. This perennial polypore grows against conifer tree trunks in a columnar shape that can reach up to one meter in height. Fomitopsis officinalis was used to treat many ailments. But a significant use of this fungus was revealed only recently. What scientists once thought were carved wooden figures were revealed to be carved of F. officinalis fruiting bodies! These figures were used to guard the graves of shamans. After a shaman’s death, the carved fungus figures were placed at the head of the grave in order to send a message that the grave was occupied by spirits. [Editor’s note: we’ll take a closer look at this species in the next post…]

There’s still much to learn about the uses of fungi by indigenous peoples of North America. It’s clear that these living things were perceived as powerful and mystical objects, and played an important role in Native American culture.

lately in the public lens

I’m camera shy, but I’ve been popping up in various media these days, mostly giving laid back, image-rich talks to welcome people into the fungusy world that you and I love. Thought you might be curious.

My popular lecture for Cornell’s Summer Lecture Series is available via a CyberTower webcast (too bad you can’t hear the great audience, who gamely answered my questions and laughed at my jokes).

A Visit to the Mushroom Planet

A fun new radio interview with Jenny Nelson for Science Cabaret on Air. I gave a Sci Cab presentation a few years ago with Kent Loeffler and Tim Merrick. That is not online (you just had to be there, drinking beer):

Fungus Amongus

My friend Dr. Tim Baroni and I recently gave a tag team presentation as a SUNY Cortland Community Roundtable which is now up as a webcast:

Fungus Among Us: Mushrooms and Molds in Our Lives

I joined a live discussion of fungi (and how horrible and creepy they are!) on Connecticut Public Radio’s Colin McEnroe Show (Jan 11 2010):

CMS: Mushrooms are Mysterious

And the Fungi of China collection I told you about a while ago has finally gone home, to some fanfare. Here is the final installment:

Prized Mushroom Collection Returns to China (Associated Press)

More details on China chez nous.

happy mushrooming,

Kathie Hodge

Puffballs ate my mulch

In which your Editor, Kathie Hodge, speaks lovingly of the puffballs in her yard.

I’m not a very good gardener, despite good intentions. That’s why I have a pile of bark mulch that I never got around to spreading. At first it stood as a testament to my indolence; a reminder of horticultural shame as I passed by every morning and evening. How I despised it! But then it started growing puffballs.

Not just a couple of little puffballs either, but a massive, tumorous pile of them. A burgeoning puffball eruption! At night I could hear them muttering at each other (hey, heeyy, heeeyyy) as they shouldered themselves some room to grow. They really like my mulch.

Although collectively huge, these aren’t giant puffballs, they’re just “ordinary” puffballs. They don’t need water to disperse their spores like normal mushrooms; their spores get puffed out by deer hooves, drops of rain, scampering chipmunks, and the stomping shoes of certain children I know.

Puffballs are funny fungi that seek to offend. You might know them as members of the genus Lycoperdon (we’ll revisit this later). That name derives from the Greek words for wolf and fart. (Yes, I said fart on the internet. Sorry Mom). More about farts and the names of puffballs in many languages in the famous book, Mushrooms, Russia, and History, which you’ll want to read. I’ve never smelled a wolf fart, and I suspect one should generally avoid getting close to a farting wolf. One shouldn’t inhale the puffs of these puffballs either. To do so would be to risk lycoperdonosis (which I guess translates to wolf fart disease). There aren’t too many documented cases of this, it’s not like you can get it from a single stomp. But poofing some puffballs right into your nose will do it. A generous lungful of spores will result in breathing trouble, fever, and pulmonary damage. These symptoms can take months to clear, but as far as I can tell, they appear to arise from hypersensitivity and inflammation rather than fungal growth in the lungs. You will not be eaten by puffballs as if you were a big mulch pile.

Lycoperdon might be one of the coolest fungus names ever (cast your vote here!). But alas, my mulch puffballs are no longer Lycoperdons. You see, mycology is in the midst of the biggest revolution since Elias Fries sorted and named everything (C.H. Persoon was a help too, particularly amongst the puffballs). We’re using genetic information to sort things out now. These puffballs turn out to be genetically distant cousins of the true Lycoperdon species (like L. perlatum). They’re morphologically different too, and they like to eat wood more than other Lycoperdons. Different enough that Kreisel and Krüger have moved our mulch puffballs into the genus Morganella, where they can hang out with closer kin. So now we must learn to call these wood-eating, often pear-shaped puffballs Morganella pyriformis.

Now a word for you, you mulch people. You are better gardeners than me; I admire your lovely, tidy gardens, your muddy knees. You are thinking about writing to me, aren’t you? To ask how to kill the puffballs that are eating your mulch? So it’s back to basics then: What’s mulch for? A cover for your lovely rich soil that you have worked so hard to build. It cuts down on erosion, suppresses weeds, maintains moisture, and… and what? Provides nutrients for your pretty little plants as it breaks down to form humus. So don’t ask me how to get rid of puffballs. They are breaking down your mulch (a euphemism for eating it), but in the process they are feeding your plants and building your soil. The puffballs are your friends. If you really don’t want your mulch to break down, try plastic. But unsubscribe me from your fan club.

To sum up: Coolest name ever, but this lignicolous species has been exiled from the wolf farts. Snorting them leads to lycoperdonosis, which I suppose is a misnomer if we’re Morganella now. Stomping is fun; hold your breath. Mulch people: love thy mushrooms. Puffballs, eat your mulch.

The fungus you want in your walls

This post was written by a clever student who took my new Medical and Veterinary Mycology class in 2009.

“The fungus you want in your walls.” Now that’s a phrase I’m sure you never thought you would hear. With the threat of certain fungal species associated with sick building syndrome becoming an increasingly common concern… who wants fungus in their walls? Well the minds behind Ecovative Design are intent on convincing the world that everyone should have fungus in their walls, and in their packaging. From what I’ve read, I’d have to agree and I’d like to share what I’ve learned with all of you.

Ecovative Design is exactly what its name suggests; a company using ecological knowledge and innovative techniques to design eco-friendly substitutes for common products. Ecocradle® Packaging is a green alternative to traditional styrofoam packaging and Greensulate® is an alternative to traditional insulation for housing. The company was launched in 2007 by two graduates of Rensselaer Polytechnic Institute, Eben Bayer and Gavin McIntyre. Their idea of changing the way common materials are made has become a working reality through all of the grants they have won. I find their achievements and ingenuity impressive. It takes a lot of hard work and unique thinking to create and run a company with an ambitious goal, especially in this economic climate.²

Ecovative Design’s products use natural ingredients to grow biodegradable alternatives to insulation and Styrofoam packaging. In their products, bulking agents–husks and hulls of various commonly grown food stuffs–are held together by fungal mycelia. The idea to bind natural products together this way was sparked by an interest in the way fungi bound wood chips. It was a simple observation, but it opened a curious mind to new possibilities. It turns out that the use of a fungus is key to the production process. The enzymes that the fungus secretes and the filamentous structure of mycelium convert lignocellulosic waste into a cohesive product. By maintaining a controlled micro-environment Ecovative Design can grow their products in an approximately week long process. The versatility of fungal enzymes allows for many different types of husks and hulls to be used in the production process, allowing for specialization in production based on region. Cotton hulls can be used in one region where they are a common waste product; soy growing regions can exploit soybean hulls. Ecovative Design looks to not only produce a green product, but to make the whole process as eco-friendly as possible.²

Ecovative Design’s products are made possible by the unique way that fungi grow. The growth of mycelium is key. Their fungus belongs to the phylum Basidiomycota (a group you know, since it includes mushrooms, bracket fungi, and stinkhorns, among others). The company specifically uses a fungus capable of producing dimitic or trimitic hyphae. These types of fungi contain two or three different types of hyphae respectively (which fungus? that’s proprietary info). The different types of hyphae give the growing fungus different characteristics, such as increased thickness or strength. All fungi create generative hyphae, but some can also make skeletal hyphae or binding hyphae.¹

In case you were thinking of your spore allergies: The fungi are rendered inert, unable to continue to grow or produce allergenic spores, by a key step in Ecovative Design’s production process. The production and stabilization of Greensulate® and Ecocradle® prevents the fungi from producing spores.²

I’m sure you’re also concerned about how the Greensulate® handles traditional standard tests for insulation products. This I found really interesting. Greensulate® stands up better to fire damage than traditional insulation. This can be seen in a snippet of an interesting video that Ecovative Design made for the Google 10^100 Project. But dried basidiomycete mycelia are highly combustible, so how is Greensulate® fire retardant? It’s the bulking agents within the insulation rather than the fungus that makes the product fire retardant. The bulking agents, a combination of rice husks, buckwheat hulls, and cottonseed hulls, have a naturally high silica content that prevents the product from burning readily. The Greensulate® product also meets current standards for flood damage and behaves similarly to lumber in these tests. One test found that the material absorbed less than 8% water by mass while maintaining structural integrity. Greensulate® also performs similarly to lumber in tests of resistance to fungal growth. The ability of Greensulate® to resist fungal growth is achieved by the addition of a boride solution, but less is necessary in Greensulate® than in traditional cellulose insulation.²

I’m thinking Ecovative Design is definitely on the right track. It’s exciting to see young entrepreneurs putting fungus to good use in a new way, and I hope to hear more about this company in the future. Keep on the lookout for more news about Ecovative Design, as they continue to win grants and awards for their eco-friendly and innovative ways. I don’t know about you, but I’m ready for people to be excited to have fungus in their walls and as an alternative to petroleum-based packaging.

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