Fungi, Mushrooms, and the Mycelial Web: The Great Collaborators
Coming Back to Nature: Science Rich Activities for Children and Their Adults
Note: This blog is a serialization of a book titled Field Trips for All of Us: Transformative Adventures for Children and Their Adults. Here is the preface. The first field trip is Taking Education Outside.
Introduction
One way of classifying life on Earth involves sorting living beings into five kingdoms. Almost everyone is familiar with two of these kingdoms: plants and animals. The third and final kingdom with visible multicellular members is Fungi. All life on Earth is interdependent, and ecosystem relationships are often mutually beneficial. Members of the fungal kingdom make this abundantly clear! Plants may never have made it out of the sea without fungal partners. Many forms of fungi form amazing mutual relationships with plants. Lichens are composite organisms with fungal and photosynthesizing members (algae or cyanobacteria) so tightly bound together that they reproduce as one. In this field trip, you’ll guide your kids in search of fantastic fungi and learn some remarkable ways they relate to the rest of life on Earth!
Warning: Fungi are fantastic organisms and many species produce mushrooms that are beautiful, otherworldly, edible, and medicinal. About 3% can also kill you. Please make sure you and your children. Do not eat any mushroom unless you are sure that it is an edible species! For kids, we always say, “do not eat anything unless it is prepared and plated by an experienced adult!”
Activity
Mushrooms grow in a variety of habitats. They typically require a relatively moist environment and grow from unhealthy or dead trees or directly from the soil. There are four visible forms of fungi: mushrooms with caps and stipes, mushrooms without distinct caps or stipes, mycelial rhizomorphs, and lichens.
Looking for Mushrooms with Caps and Stipes
When we think of fungi, most of us think of mushrooms, and when we think of mushrooms, we think of mushrooms with stems and caps. Fungal enthusiasts call these mushroom parts the mushroom stipe and pileus. I usually carry a pocket mirror with me when I’m mushroom hunting so I can look at the underside of capped mushrooms.
While you’re out and about with your kids and a hand mirror, pay attention to the forest floor, decomposing logs, leaf litter, and soil. If you find mushrooms with caps, use your mirror to examine the underside of the mushroom. Most likely, you’ll see one or more of three forms of capped mushrooms.
Gilled Mushrooms: When most people think of capped mushrooms, they think of one with gills on the underside of the cap.
Boletes: While gilled mushrooms produce spores on their gills, boletes produce them in vertical tubes under their caps. These tubes are packed together and give the underside of boletes a spongy feel.
Chanterelles: These capped mushrooms are shaped like trumpets or vases. Their caps are often wavy and most varieties are yellow or orange. They produce their spores on ridges that look something like gills.
Morels: A choice edible with toxic look-alikes. The caps on morels have an interesting honeycomb appearance.
Making Spore Prints
Making spore prints is a fun and important part of identifying mushrooms. It is a relatively easy process with most gilled mushrooms, boletes, and chanterelles.
Place one or more mushrooms cap up on a piece of tin foil or white paper. Put a few drops of water on the top of the cap to help the mushroom release its spores. Cover each mushroom with a cup and wait twenty-four hours.
Spore prints often make interesting patterns and their color is important in identifying mushrooms. Spores play a similar role for mushrooms as seeds do for plants.
Looking for Mushrooms without Stipes and Caps
This group of mushrooms lacks either or both stipes and caps. Many are edible but again, don’t think about eating them unless you are 100% certain of their species. These mushrooms grow in the same kinds of environments as mushrooms with caps and stipes.
If, while out and about, you find mushrooms without caps or stipes or both, note their shape and where they are growing. Most likely, you’ll see one or more of five forms of non-standard mushrooms.
Polypores and Shelf Mushrooms: These mushrooms grow on tree trunks forming shelf-like structures. These structures sometimes develop in stacked layers. Chicken of the Woods is a choice edible polypore and Turkey Tails are valued as medicinal by many cultures.
Puffballs: A favorite of children because when they’re mature and you squeeze or kick them, they release their spores in a puff of what looks like dust. As their common name implies, these fungi are ball or sometimes pear-shaped and grow mostly in soil, although they also grow from decaying wood.
Jelly Fungi: Jellies are a fun mushroom type. As their common name suggests, these fungi have a jelly-like consistency and appearance.
Corals: Another mushroom with a very descriptive name. These grow in branched structures that resemble sea corals. I find them most often growing from the ground. They also grow on decaying wood.
Toothed Mushrooms: Not surprisingly, this group of mushrooms is known for their teeth that hang down from their caps, such as Lion’s Mane.
Looking for Rhizomorphs
Mushrooms are often called the fruiting bodies of some kinds of fungi. They are called fruiting bodies because they, like fruit, are how some fungi reproduce. Not all multicellular fungi produce mushrooms. All do form mycelium though! Mycelium are web-like structures formed from, hyphae, the basic building block of all multicellular fungi. Hyphae are long tubular structures that each contain one or more fungal cells. Mycelial webs are not usually visible without magnification. Some types of fungi develop thick bundles of hyphae that look like plant roots. You might see these in your planted pots or raised beds. These structures are called mycelial cords or rhizomorphs depending on their complexity.
Wander the woods with your hand lens in the wettest areas you can find and look on the surface of decomposing wood, under the bark, or between logs and soil. I’ve also found them or very dense mycelial webs (hard to tell with a microscope) inside very decomposed wood.
Looking for Lichen
I have one tattoo. It’s a picture of a kind of lichen called Usnea. The picture is encircled with the phrase, powered by diversity. Why? Lichens are composite organisms. They are a lifelong relationship between a fungi and a photosynthetic microorganism partner: either an algae or a cyanobacteria.
While sauntering in the outdoors, keep your eyes open for lichen. Lichens in general are very tolerant of cold and dryness. If conditions make where you live generally unfriendly to fungi, you may still be able to find lichen. They are usually some shade of green owing to the photosynthesizing member(s) of the team. As a rare organism that can digest rocks, they are often found growing on boulders or trees.
Lichens form visible macroorganisms of one of four kinds.
Fruticose: These lichens branch and look like mini trees. My three favorite lichens are all of this form. Reindeer Lichen is edible and is indeed eaten by reindeer. Usnea is a choice medicinal and is featured in my tattoo. Wolf Lichen is a cool green fruticose lichen that is common where I live now in the mountains of Southern California. It’s also generally found in the Western USA and Europe.
Foliose: Foliose lichens have leaf-like scales that are not bonded to their growth substrate. The term comes from the Latin word foliosus, which means leafy.
Crustose: As the name implies, these lichens generally form a crust on their substrate and are bonded to that substrate. Crustose lichens can be a variety of colors including yellow, orange, and red.
Squamulose: These lichens are in between crustose and foliose lichens in appearance. They form scales that are smaller than those of foliose lichen.
Nature Science
We’ve focused on visible members of the fungal kingdom here. Yet, much of what goes on in the fungal kingdom is invisible. Invisible fungi include single-celled varieties like yeast. Yeasts are important to us humans as one of the main kinds of microorganisms responsible for making bread rise and brewing alcohol (see Teaming with Microbes to Create a Sourdough Starter for more on this topic). Hyphae, the basic structural unit of most multicellular fungi, are also invisible. Hyphae are tubular and contain one or more fungal cells within a rigid structure. Hyphae form vast networks called mycelium. Mycelium is also not usually visible except when it grows very densely or forms into rhizomorphs.
Saprophytic fungi play a major role in ecosystems. As decomposers, they are instrumental in returning nutrients to the soil and in maintaining soil health. Very few organisms other than fungi are capable of digesting lignin, a major structural component of plants that, along with cellulose, gives trees their structural strength. Mycorrhizal fungi form the most amazing mutual relationships with plants (the prefix myco means fungi, and rhiza means root). The fungal mycelium (threads of interlocking hair-like fungal cells) either enters roots (endomycorrhizal) or wraps around them (ectomycorrhizal), and both supply minerals to and receive sugars from the plant. This is not rare in ecosystems. Many trees and other plants in forests are intertwined with each other via vast mycelial webs. It’s likely that early plants lacking roots first survived on land through these kinds of fungal partnerships. If this kind of relationship seems deep, consider Lichens. They may be the most astounding fungal collaboration. They are composite organisms with fungal and photosynthesizing members (algae or cyanobacteria) so tightly bound together that they reproduce as one.
In our post, We’re All Related, we introduced the idea of formal taxonomies. We did not discuss formal mushroom taxonomy here. Why not? Because new techniques in genetics and advances in the study of systemics have blown the field of mushroom taxonomy wide open! Up until 1969 mushrooms were considered plants! Fungi were originally classified based on their morphology (i.e., structure) much as we did here. Check out mycologist Alan Rockfeller and his DNA sequencing research for more information.
We all find our poetry in different places. One place I find mine is in the rhizosphere, where roots, tiny crystals, grubs, bacteria, fungi, nematodes, worms, poop, pee, decaying parts of bodies, and exudates all gather and make beautiful biological music together. What I remember from school was a description of how plants extract raw materials from the soil and atmosphere much like humans do. What a sad individualistic story. The truth is more of a 24/7 flow of gifts between three types of contributors.
To start with plants, animals, and fungi all need water, simple nitrogen-based molecules, sugars, and minerals, to continually rebuild themselves.
Plants, as we’ve all been told, pull carbon dioxide from the air and with the energetic help from the sun, create sugar for itself through a process called photosynthesis. They can’t make their own simple nitrogenous molecules though.
Nitrogen-fixing bacteria are great at, well, fixing nitrogen. That means they can make simple nitrogenous molecules like ammonia (NH4) nitrates and nitrites (salts containing NO3- and NO2- respectively) from atmospheric nitrogen. These molecules are critical intermediaries used by the bacteria (and the rest of us) to build proteins, DNA, RNA, and other biomolecules. Neither fungi nor plants can do this. Bacteria can’t, however, synthesize sugars.
Mycorrhizal fungi (fungi that dance with the roots of plants), with their vast webs of mycelial fibers, are great at gathering water and minerals they and other beings need. However, they can’t synthesize sugars nor the simple nitrogenous molecules they and other beings also need.
So, how do our players use their gifts together?
Our mycorrhizal fungi and nitrogen-fixing bacterial friends are both drawn to plant root hairs by the plant's gift to the team—sugary exudates the plant generously leaks from its roots. Some of the bacteria gather close to the roots, stimulating the plant to grow tiny (but often visible) root nodule homes for their microbial friends. There, they drink in the plant's sticky gift and do their nitrogen-fixing things, their residual nitrogenous compounds becoming gifts for the plant. The mycorrhizal fungi either wrap their delicate mycelial filaments around or gently enter equally delicate root hairs. There, they exchange minerals and water they have gathered, for sugar synthesized by the root’s plant. This is not about factory-like extraction but instead is a microcosm of the forest above. A full-time dance of interdependence!
The thing that is most amazing about these relationships is that they are non-transactional. There is no quid pro quo in the rhizosphere! Materials and energy are passively and actively transferred across the fuzzy edges between species from areas of higher concentration to areas of lower concentration. That, in and of itself, seems unremarkable. What is remarkable is that the result of this bi-directional flow is the kind of relationship that Karl Marx recommended in 1875 when he said, “from each according to his (sic.) ability, to each according to his need.” The other amazing thing about this bi-directional flow of resources is that giving leads to getting, and giving more, leads to getting more (up to a point, of course). Wouldn’t it be wonderful if people related to each other and the rest of the natural world in a way that resulted in the relatively equal distribution of resources and increasing abundance?
Educational Ideas
As is true with most of our posts, this is not a lesson plan or even an activity plan in the conventional sense. We see mediating between things we want the kids to make sense of, their interests and experiences, and what’s happening in our ecosystem as one of our roles as adults in a natural learning environment. I go into the day with some big ideas in mind and some suggested activities based on the weather, what we did last week, and what the kids seem to be drawn to. Some big ideas that fit well mushroom hunting are:
We are all in this together as members of a global ecosystem. Like all living and nonliving (i.e., abiotic) features of ecosystems, humans are ecosystem contributors. We all give and receive matter, energy, and information from each other and thus directly or indirectly interrelate and are interdependent. We humans of the global north must relearn how to benefit rather than harm each other and poison our environment.
It’s all about relationships! Both living and nonliving things exist in relationship to each other. Things have both spatial relationships with other things (e.g., under, over, next to, connected) and material exchange (e.g., chemical) relationships with each other (e.g., getting carbon dioxide from and giving carbohydrates to). Many chemical and physical relationships depend on spatial proximity (i.e., closeness). Systems are formed from things in relationship to each other that act together. Patterns that connect are common repeating relationships. See, Observing Relationships in Nature for more on this topic.
Relationships in ecosystems tend to minimize harm. Many material exchange relationships in ecosystems are mutually beneficial. Those that aren’t including competitive, consumptive, predatory, and parasitic relationships tend to minimize harm.
On any given day I might have these ideas in mind. During circle, I might suggest we hike and keep our eyes open for mushrooms, rhizomorphs, and lichens. The kids might suggest alternative activities. Then we see what happens. Alternatively, I might have other ideas and activities in mind and we might bump into some fungi and start exploring and talking about them. I’m used to thinking of my role as facilitator, guide, and activity coordinator. And, more and more I see mediation as a central role for adults in learning environments. There are such interesting similarities between mediating a conflict of interests between the kids and mediating between big ideas I think are important and the kind of activity they like to engage in.
Wrap Up
Ecosystems are a dance of interdependence. Nothing makes this more obvious than fungi. Looking for mushrooms, rhizomorphs, and lichens provides lots of great opportunities to learn more about these fascinating organisms and generally about how ecosystems work. This field trip is in no way a complete guide to mushrooms or mushroom identification. We could spend the rest of our lives studying mushrooms and we’d still have more to learn. There is a lot of information about mushrooms and fungi on the internet. We recommend checking out Travis Kriplean’s post, An Informal Program to Learn Ecoliteracy with Kids through Mushroom Foraging. It’s a beautiful description of how Travis works with kids around mushrooms. It also includes some other useful links. Mycologist and Mushroom Expert are good sites for helping identify mushrooms as is WildFoodUK. Mycologist is also very useful for learning more about fungi in general.