Water drops on plants

Gardeners sometimes see leaves fringed with droplets of liquid. The droplets are not dew or rain, and plants don’t sweat. So what are they? Those drops are a way for the plants to excrete excess water, perhaps taken up from very wet soil or resulting from metabolic activity. They are produced mostly at night. During the day, water is drawn up through the plant and evaporates from openings (stomata) on the leaf surfaces. Stomata often close at night, but root pressure still forces some water up to the leaves and out pores at the leaf edge. Production of those droplets is called guttation (from the Latin word ‘gutta’ for a drop).

Guttation drops contain not only water but also sugars, proteins, and probably minerals. The additional substances are associated with a variety of interesting interactions, nutritional, protective, or otherwise.

A recent study examined the guttation drops of a blueberry species native in eastern North America. In this case, the drops were produced both day and night, especially during shoot and early fruit development. Researchers tested the survival and egg production of three insects (an herbivorous fly, a parasitic wasp, and a predator) on a diet of guttation drops compared to diets of water plus sugar or protein (or both). Sugars and proteins contributed to longevity and fecundity: Survival was better on guttation drops or sugar water for all three insects and for the predator on sugar and protein also. In general, females produced more eggs on guttation drops and on sugars plus protein. In short, guttation drops were indeed nutritious, providing useful nutrients.

Furthermore, there were effects on the arthropod community. Lots of arthropods visited the drops on plants in the field. The most common visitors were ants, fruit flies, lacewings, crab spiders, and parasitic wasps. Researchers set traps near plants with guttation drops and those without drops. More predators and parasites were captured in traps near plants with guttation drops, although herbivores were not affected. Given that the production of drops in this blueberry is unusually reliable for a period of time, it seems possible that the drops contribute to biocontrol of pests.

In other cases, the guttation fluid might contain certain proteins that would protect the plant from motile microbes on the leaf surface that could invade the plant through the leaf-edge pores. Another study noted that grasses are often associated with symbiotic endophytic fungi that grow in the inter- cellular spaces and produce alkaloids that help protect the grasses from grazers; in some cases, the alkaloids get into the guttation fluids, where they might provide additional protection. On the negative side, there’s a certain kind of bacteria that causes disease in tomato plants and gets into guttation drops; any contact with a contaminated drop can then transfer the disease to another tomato plant. Corn plants germinated from insecticide-coated seeds produced guttation drops laden with that insecticide, which is lethal to honeybees (and presumably other insects) that might come to sip on the fluid.

Fungi also produce guttation drops, although the process by which they do so is apparently not known. There’s a certain fungus that attacks sugar cane, producing necrotic lesions by secreting toxins in guttation drops (just when the fungus is making spores). A fascinating interaction may occur between two facultatively parasitic fungi that can attack the same fungal host. The guttation drops of one of the parasites contains hydrogen peroxide (plus enzymes), which is generally toxic to the second parasite–and species #1 produces guttation drops chiefly when in competition with species #2 for the same feeding space on a host.

Guttating fungus. Photo by Bob Armstrong

Clearly, guttation drops can have ramifying effects on a variety of interacting species, although the possibility of such effects has not been explored extensively. There are probably lots more of these interactions still to be discovered—yet another way that plants (and fungi) can affect ecosystems!

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Fall fungi

It’s been a good fall for mushrooms and other fungi; the trail-sides have been decorated with a variety of forms and colors. One day, on the Horse Tram trail, I noticed a beautiful fungus on tree, a species of Pholiota (known as scaly-caps), probably the golden-fleece scaly-cap. It’s a wood-rotting saprophyte. Several days later, those golden caps had matured, opened, and turned gray. Most of the rest of the fungi have now deteriorated into messy lumps, but it was good while it lasted.

The golden fleece scaly-cap decorated this tree trunk for several days, before turning gray. Photo by Mary Willson

Some sharp-eyed hikers called attention to some strange-looking mushrooms that most of us have never noticed at all. These turned out to be not one but two different fungi in close association. A local mycophile identified one of the fungal participants as a species of Hypomyces. The many members of that genus are parasitic on other mushrooms, growing over the surface of the host, changing the surface color (to red or green or yellow or…), sometimes changing the shape of the host and even preventing the mushroom cap from opening for spore dispersal. The parasite sends filamentous hyphae into the body of the host and extracts nutrients.

A parasitic fungus in the genus Hypomyces covers another fungus, probably Russula. Photo by Deana Barajas

Each species of Hypomyces parasitizes just certain kinds of fungi—some on Amanita, some on Russula, some on Helvella, and so on. Many, perhaps most, of the hosts are mycorrhizal, forming mutualistic connections to various plant species and often connecting one plant, of the same or different species, to another. Those connections move materials among all the participants. When the parasites tap into those connections, it opens up the possibility that some nutrients from plants might end up in Hypomyces—which thus might be indirectly parasitic on plants. This adds a whole ‘nother layer of complexity to existing connections.

Of course, there are lots of questions to be asked about these complexities. Could the parasite, by drawing nutrients from the mutualistic host fungus, perhaps increase the movement of nutrients from the plants? How does that possibility affect the mutualism? Do the species of plants connected to the host fungus have an effect on growth and reproductive success of either the host or its parasite?  Hmmm, the ecology of Hypomyces is rife with unanswered questions!

In early September, a cheery little roadside plant was still flowering. It’s called eyebright, for its medicinal applications, and belongs to the genus Euphrasia. When I tried to look for more information about this genus, I found that the taxonomic complexities daunting. There are many species in the genus; they often hybridize and populations have evolved in different directions rather rapidly. Furthermore, the genus (with its many relatives such as paintbrush, lousewort, yellow rattle) has been transferred from one taxonomic family (Scrophulariaceae) to another (Orobranchaceae). So we need to update our field guides!

Eyebright blooms for many weeks, well into the autumn. Photo by Mary Willson

Like its just-named relatives, eyebright is hemiparasitic. It has green leaves and can photosynthesize its own energy-yielding sugars but it also makes connections between its roots and the roots of various host plants, often grasses and other herbaceous species. The host plant can affect the size and the time of flowering of eyebright, and perhaps other aspects of its life history.

Our local species is known as Euphrasia arctica. It’s a tetraploid (with twice the usual amount of DNA in its nuclei), so it may have originated as a hybrid. An annual, it often colonizes roadsides and other disturbed sites. The little white flowers are probably self-compatible but potentially out-crossing. The flowers may be visited by insects, but I’ve seen little visitation on the plants I’ve looked at. The fruit is a small capsule, with many tiny wind-dispersed seeds.

Thanks to Jenifer Shapland for identifying the fungi.

Dispersal of fungal spores

Many fungi disperse their spores by releasing them from gills or pores into the air, for breezes to carry them away. Insects can carry some fungal spores either inside or outside their bodies, and almost any mammal that eats an occasional fungus can probably do so. Indeed, mammal-dispersal of fungi occurs in a variety of habitats ‘round the world. This mode of spore dispersal is especially important for fungi such as truffles, which are chiefly subterranean. There are thousands of species of truffle, and they apparently depend on animals that dig them up and eat them, passing viable spores through the digestive tract, and depositing them at some distance from the parent along with nutrients from digested foods and useful bacteria. This foraging habit is an essential component of many ecosystems, because truffles are mycorrhizal fungi that form mutualistic associations with many plants, providing assorted nutrients from the soil in exchange for sugars from photosynthetic plants.

In the western forests of North America, fungal spores can be dispersed by deer and mountain goats and many kinds of rodents, including chipmunks, red-backed voles, marmots, pikas, and others. But it seems that flying squirrels get the most notice (judging from the number of published reports).

A flying squirrel foraging for fungi. Photo by Bob Armstrong

Birds get into this act too; there are scattered reports in the literature of birds that eat fungi. Dozens of species eat fungi, including quail, ruffed grouse, wild turkeys, and free-range chickens, in North America, but the role in spore dispersal is not recorded. A few fungus-eating species are known to eat truffles:lyrebirds in Australia scratch up the litter and topsoil to gettruffles and other fungi; Australian eastern yellow robins often forage in such disturbed areas and eat left-over truffles; migrating birds in Kuwait eat truffles in the desert. They probably disperse the fungal spores, but good documentation is lacking.

Recently, however, there’s a fulsome report about fungus-eating birds in the south-temperate rainforest of Chile and Argentina. That rainforest is quite different from our local one in many ways; of particular relevance here is the presence of several bird species that typically and regularly forage on the ground. These include the austral thrush and several endemic species of tapaculo that are known to eat fungi. This report focused on the black-throated huet-huet and the chucao (tapaculos whose nesting biology I studied many years ago). These birds often run around on the forest floor, scarfing up bugs and fallen fruits and—it turns out–scratching up and eating truffles.  The researchers genetically screened the birds’ fecal samples and found that many species of fungus, including truffles, had been eaten. Special microscopic examination of the feces revealed large quantities of viable fungal spores. Many of those fungal species are mycorrhizal, associated with the so-called southern beech trees of that rainforest.

Although our local forests don’t feature so many forest birds that habitually forage on the ground, it would be interesting to know if any local birds sometimes contribute to fungal spore dispersal. Grouse have well-developed gizzards that might grind up spores along with seeds, but perhaps some of the tiny spores get through the gut. Robins and varied thrushes scuff up moss layers and might sometimes find fungi to be edible. And what about flickers, the woodpecker most likely to forage on the ground; we sometimes see it probing down into the mosses. Or crows and ravens, which love to poke about under moss and stones and sticks.

Three fungal curiosities

This essay is about an eclectic assortment of fungi, my choices being based entirely on happenstance and whim.

One September day on the Outer Point trail, we spotted a very large, yellowish patch on a tall alder snag. That patch covered most of one side of the snag; at a guess, it may have exceeded ten square feet. At first glance I thought it was a huge crustose lichen, but no, it was a fungus. On certain places on this expansive crust, there were small ridges like miniature conks, and on their undersides were numerous pores where spores would be produced. The crust has covered mosses and engulfed the stems of licorice ferns.

Photo by Jennifer Shapland

I went back to look at it about ten days later, and now the surface featured many shallow furrows that had turned brown. The furrows were four or five millimeters wide and several inches long, crisscrossing the flat surface of the big fungus. Were they the work of slugs or land snails, grazing their way along? No, there were no marks of the scraping radula or tongue. A few days later, another observer suggested that wind-bent branches hit the fungus. No, when I tried it, small branches striking the surface didn’t leave furrows like that. A few more days later, we finally noticed that all the furrows occurred between human knee height and head height. Then I found that I could mimic the furrows very well with the flat of a fingernail. So we—finally!– concluded that these furrows are just graffiti. Much less interesting than slug trails, but perhaps closer to truth. ‘Twas a shame to deface such a beautiful organism.

What is this magnificent, hall-of-fame specimen? It seems that nobody really knows! It might be X or maybe Y, or something else altogether. Several mycologists have been consulted, with no concrete results. A sample sent to a lab for DNA analysis might yield a solid answer.

A strange fungus sometimes seen near the visitor center, among other places, is called the bleeding tooth fungus (Hydnellum peckii). Its name is not about bleeding teeth; it’s a tooth-fungus (with spore-bearing ‘teeth’ instead of gills or pores) that seems to ‘bleed’. The immature cap is white, but sometimes there are little pools of red fluid on the surface. Another name, perhaps for the more squeamish observers, for this critter is strawberries and cream. As far as I can tell, nobody really knows why those pools form on the cap. The present idea is that it’s a way to get rid of excess moisture, as some other fungi and some plants do by exuding droplets of water. But why are the pools red? Is the color just an incidental by-product of some metabolic process?

Photo by Jos Bakker

This fungus is mycorrhizal, forming connections with the roots of conifers and exchanging nutrients. The cap turns dark as it matures and produces spores. The stalk is thick and short, so short that the cap is often semi-buried in moss and debris. That raises the question of how the spores get dispersed from under the cap.

Yet another curiosity is a bird’s nest fungus (Nidula candida), a decomposer living on dead wood and rotting vegetation that is quite common around here. It earned its name from its appearance: the mature, reproductive form features a small (roughly one cm) cup containing several little round (somewhat flattened) objects. So it resembles a miniature bird’s nest with eggs. The ‘eggs’ contain spores. The cap is ingeniously built so that a raindrop can splash the ‘eggs’ out of the cup to a distance of a meter or more. The ‘eggs’ of some bird’s nest fungi (but not ours) are ejected with long, sticky threads, which catch on vegetation as they fly off. Eventually the ‘eggs’ deteriorate, releasing the spores. The spores germinate, producing stands called hyphae; two hyphae of the right mating type can merge to develop a nest-like fruiting body. Splash-cup dispersal mechanisms are uncommon means of spreading offspring around, but they are known also from some plants.

Photo by David Bergeson

Fungi!

There are tens of thousands of fungal species, which are classified in a kingdom all their own, neither plant nor animal. We become acquainted with some of them in unlikable ways, when they infect us or show up as mildew on our roses. Although we bemoan those fungal invasions, other fungi have been useful to humans in many ways.

Just consider, for a moment, what our lives might be like in the absence of fungi. There wouldn’t be yeast-leavened bread, so no hot-cross buns, chocolate eclairs, or ordinary pb&j sandwiches. No beer or wine, so although South Franklin Street might become more attractive, New Year’s Eve parties might be staid and quiet—and the highways would be much safer. Without penicillin and other antibiotics derived from fungi, we (collectively) would a lot sicker and maybe, in some cases, dead. Some folks would miss the hallucinogenic fungi and many would rue the lack of delectable chanterelles and boletes. Those that create fabric items would miss the many hues of dyes derived from fungi.

Of more fundamental importance, however, are the ecological roles of fungi. Many fungi form connections with the roots of trees, shrubs, and herbaceous plants, providing nutrients from the soil to the plant in trade for carbohydrates from the plant’s photosynthesis. These mycorrhizal fungi contribute significantly to the health and growth of the partnered plants. Our forest would be a poorer place without them!

Thus the fungi give, but they also take away: They are major decomposers of plant and animal matter. If dead trees and leaves didn’t decompose, ultimately the forest floor would be buried and no understory could grow. So, no winter food for deer, no high-bush cranberries or blueberries. Leaves and stems of dead grasses and sedges would make a thick, impenetrable mat over the meadows. Perhaps the only places new trees or grasses could grow would be on recently exposed bare soil (think of receding glaciers, landslides, post-glacial uplift), and then it would be only certain kinds of plants that could cope with conditions there. Furthermore, we’d be surrounded by carcasses of dead animals and small trailside mountains of dog poop that would be only partially diminished by bacterial action.

The activities of fungi sometime appear in unexpected places. For example, recent research has shown that fungi play a role in the formation of hair ice—those wonderful curls of extremely slender filaments of ice (only about one hundredth of a millimeter thick!) that emerge from sodden branches when the temperature is just below freezing, and the air is humid and still. This story has a beginning over a hundred years ago, with Albert Wegener, the astute fellow who recognized the fact that the continents move around. In addition, he noted that hair ice appeared on damp branches of deciduous trees and shrubs that were also laden with fungi; he then surmised that the fungi had something to do with the formation of that hair ice. After a long delay, recent research has confirmed that surmise. Although those old, wet branches harbor several kinds of fungi, one in particular is consistently associated with hair ice. That fungus (Exidiopsis effusa) is a decomposer of wood; it somehow also shapes the ice hairs, preventing the tiny crystals from coalescing into bigger ones. Organic matter in the hair ice, such as decomposed lignins from the wood, might be involved, but that remains to be determined.

Scientists have also discovered a new genus and species of fungus that has medicinal value, known and used in Chinese folk medicine for hundreds of years. This fungus grows on a certain kind of bamboo, as do other species in a related genus. These fungi contain compounds called hypocrellins, which are effective against viruses, bacteria, and fungi, when they are activated by light. And now we know that this new species does too. It just took science a while to catch up with traditional knowledge…

Mushrooms at Crow Point

A walk on the Boy Scout beach/Crow Point trail is almost always rewarding. There’s a variety of habitats, each of which changes with the seasons in its own way.

In late September, there were no geese to be seen in the big tidal meadow or in the river’s estuary. A northern harrier in brown plumage (female or juvenile) coursed low over the river and meadows, spooking at least one crow. A bit above the highest part of the beach, the last flowers of wild strawberry shone on a background of dark green. Several flocks of pine siskins flitted over the seed heads of meadow plants or zoomed between stands of conifers.

On the way from the parking lot to the beach, in the first riverside meadow, the trail had previously been re-routed to accommodate bank erosion. But this time, another large chunk of the bank had fallen into the river, leading to another trail diversion.

Rather than walk the long beach, I chose to weave my way in and out of the spruce groves that line the berm along the shore. These groves sometimes produce interesting finds, such as a bear skeleton or a flourishing stand of orchids.

This time, it was a mushroom show. I know next to nothing about mushrooms, unfortunately. But I was attracted to three in particular. A medium-sized brown one typically grew in long, curved chains. Troops of very small white ones clustered between spruce roots. (I called these ‘armies’, and a friend saw them as pilgrims on a mission, but ‘troops’ is an accepted informal term, I’ve read). My favorites were tiny yellow ones with orange centers on the cap. These usually grew in troops on the berm, especially in some of the groves.

Trichloma fairy ring. Photo by Pam Bergeson

To give me some guidance, I enlisted the help of a friend who does know a lot about mushrooms, and we went out there again a few days later. We made only slow progress as we walked along, because there were so many different mushrooms to look at and discuss. There were lots of Amanita muscaria (common name: fly agaric), both red and yellow varieties. They had the customary whitish ‘warts’ on the cap—except when they’d been washed off by heavy rain. (I call the white bits scattered on the cap ‘streusel’, like the crumbly mixture often scattered on muffins or coffee cake). We found huge boletes, now aged and no longer desirable for eating by humans but other critters had been feasting. There were more kinds of brown-capped mushrooms than my old brain could begin to assimilate.

I learned that the curved chains of brown-capped mushrooms belonged to the genus Tricholoma (I decided, early on, that getting the name of the genus was enough for now; species names could wait). Tricholoma fungi form mycorrhizal associations with tree roots, providing soil nutrients to the trees and obtaining carbohydrates made by the trees’ green leaves. The long sweeping arcs sometimes exceeded fifteen feet in length. Shorter arcs made nearly complete rings. So-called ‘fairy rings’ of mushrooms are well-known in both mythology and mycology (the study of fungi), but I have not found a coherent explanation of why they form these arcs in some cases but not in others.

The numerous troops of small whitish mushrooms turned out to be of several species, mostly in the genus Mycena, but a few in the genus Collybia. They are not mycorrhizal but rather decompose fallen plant parts such as old leaves and flowers.

Those tiny, bright yellow mushrooms belong to the genus Mycena, sometimes called fairy bonnets. I would love to know why troops of these were very common in some groves but not in others.

As usual, I am left with many questions. For instance, how does a fungus decide when to produce sporing bodies? The main part of a mushroom-producing fungus is an underground network (mycelium) of thread-like hyphae; the network may be very extensive. When the time is right, the fungus puts up sporing bodies that we call mushrooms. The mushroom cap releases ripe spores that disperse, potentially starting new individual fungi. (Although they are not the same as the seeds of plants, they have the same function). But what makes one time ‘right’ and others not? This year was said to be one of great bolete production—but what were the conditions that made it so?

And why are some mushrooms purple—what is the function of that pigment? Ditto for red, or yellow, or browns. Some mushrooms have massive thick stalks, almost as wide as the cap, while other perch their caps on feeble, spindly stalks. How come? There is so much to be learned!

Thanks to Jenifer Shapland for a primer on local mushrooms.

Fungi and Wildlife

Fungi are made up of vegetative parts, which are filamentous structures that typically lie underground, and reproductive parts, which take various forms, sometimes finger-like or shelves, or commonly as mushrooms with a stalk and a cap. But some fungi never produce above-ground parts; the small, round or lumpy reproductive structures are underground—these are known as truffles.

Fungi reproduce by means of spores—each tiny spore containing the makings of a new individual. Most fungi, such as ordinary mushrooms, disperse their spores aerially—releasing the mature spores from the mushroom cap to vagrant breezes in the forest understory. Truffles do it differently: they rely on small mammals to dig them up and eat them, passing the spores through the digestive tract and depositing them in feces.

Here in Southeast, there are two major harvesters of truffles: the red squirrel and the flying squirrel. The red-backed vole also does this and other small mammals may do so occasionally. These rodents also harvest typical mushrooms, sometimes caching them, to be eaten later, after they dry. Red squirrels do this very regularly; flying squirrels in other regions cache many kinds of food but apparently they have not been recorded to do so in Alaska.

Photo by Bob Armstrong

The caloric content of fresh mushrooms is low, far lower than that of nuts and seeds. However, dried mushrooms compare more favorably, although they still average only about two-thirds of the caloric content of conifer seeds. Mushrooms are very low in fat, compared to spruce and hemlock seeds, but they can be a pretty good source of carbohydrates and protein, especially when dried. They may also provide an assortment of micronutrients such as vitamins and minerals. Fresh mushrooms can be a source of water during season dry periods.

However, the actual food value of fungi to rodent consumers depends in part on the intake rate. Taking a bite of mushroom or truffle is quick and easy. But when eating conifer seeds, squirrels have to peel back the cone scale and trim the membranous ‘wing’ from each seed before eating it. Although squirrels are remarkably fast at extracting conifer seeds from a cone, it still seems that the food intake rate would be slower than when eating fungi. The actual food value also depends on how efficiently a squirrel’s digestive process extracts energy and nutrients from the material that is ingested. Some studies of squirrel diets suggest that the digestibility of fungal tissue is considerably less than that of conifer seeds. Nevertheless, squirrels regularly eat fungi, so there must be sufficient reward to make it worthwhile.

The relationship between truffles and squirrels (and voles) is mutualistic—the mammals get dinner and the truffles disperse their spores. For truffles, the relationship is obligatory; they are dependent on small mammals for spore dispersal. For the rodents, the relationship is more variable, depending in part on the availability other food sources (for example, squirrels might eat more truffles in years when the cone crop is poor). Mushroom-producing fungi sometimes get spores dispersed by rodents that harvest mushrooms; the spores ingested are viable after passing through the rodent’s guts, so in addition to the normal, aerial means, the fungi benefit from rodent assistance. This amounts to a casual sort of mutualism in which both parties benefit but the relationship is not obligatory for either one (in contrast to that for truffles).

Now the plot thickens! Many fungi, both truffles and mushrooms, are mycorrhizal—forming mutualistic relationships with the roots of various plants. The plants provide carbohydrates to the growing fungi and the fungi supply various nutrients to the plants. In most cases, both participants in the relationship grow better with the partner than they do alone; in some cases the relationship is obligatory to at least one of the partners.

Thus, in this network of interactions, one well-developed mutualism (the fungus-plant relationship) intersects with another one (the rodent-fungus relationship). Something for everybody! A nicely tangled web!

Strolling on the Treadwell Ditch Trail

One fine day in early October, three friends set out to walk the Treadwell Ditch from the Dan Moller trail to Paris Creek. On our way up from the parking lot off Pioneer Avenue, we noted major timber cutting not far above the trail; trees had fallen over the trail earlier but had been trimmed back. The lower part of the Dan Moller trail, up to the Ditch, winds through some pretty, little meadows, but the boardwalk is in serious need of repair: there are many broken boards and popped-up nail heads. A big, sad contrast with the Dan Moller trail above the Ditch to the cabin, where the trail is in pretty good condition.

The Treadwell Ditch trail south of the Dan Moller has received a huge amount of recent work and is now in good shape, as far as Paris Creek. In addition to the big bridge over Lawson Creek, there are many new, smaller bridges that save hikers and bikers and skiers from scrambling in and out of eroded gullies. One especially nasty gully is now circumvented by a re-routed trail with steps that may be tricky for skiers and snowshoe-ers in winter. A few muddy spots remain to be ‘hardened’ by the deposition of gravel, but we strolled by a lone volunteer who was in the process of doing just that. Thanks to Trail Mix for all the good work!

We’ve been told that a bridge over Paris Creek has been planned and funded, so eventually Treadwell Ditch walkers can readily join up with the Mt Jumbo trail to the south. That will avoid the risky, slippery-log walking now required for the creek crossing and the extremely muddy informal trail that parallels the creek down to the lower end of the Jumbo trail. We did none of those things, but back-tracked to the CBJ trail down to Crow Hill.

So much for the trail report (in brief). Now for the fun stuff.

Fall is a good time for fungi of many sorts, and this trip was no exception. We were particularly pleased with the numerous delicate white ones known as angel wings. These dainty fungi grow on conifer logs and stumps, especially on hemlock. Although it is often said to be edible, it is reportedly toxic and potentially lethal for some people. Another interesting one was a small, translucent jelly fungus growing out of the softer growth rings on top of a stump.

Angel wing fungus. Photo by David Bergeson

The muskegs were awash with colors, a real treat for the eyes. The sedges provided a backdrop of lustrous golden orange. Bunchberry leaves showed off every possible shade of red. Avens leaves were deep red and high-bush cranberry leaves ranged from pink to red. Low-bush blueberry leaves gave us muted maroons and purples, and deer cabbage added some yellow and orange. We don’t have the blazingly colorful tree canopies of the boreal aspen forests or of the eastern forests with their maples and ashes, but if you look lower and think smaller, we sure do have spectacular fall colors!

In the forest, the devil’s club leaves had mostly turned yellow, brightening up the somber tones of the conifers. They were so conspicuous, I paid them more attention than I had earlier in the summer. If you look carefully at these leaves, you can observe that they are usually spaced out laterally so that they don’t shade each other. When one leaf does occur above another, there is usually quite a good vertical distance between them. That way the lower leaf still gets some light. It turns out that the bigger the leaves, the more vertical distance must separate them in order that they don’t shade each other too much, so the big leaves of devil’s club will be more widely separated than the small leaves of willows or blueberry bushes. In fact, this intuitive principle has been quantified and formalized mathematically, for the benefit of those who like such things.

Early October

The mallards on my home pond gradually molted into their breeding plumage, so I could now distinguish males from females, in most cases. Some males were already in good feather for breeding, while others lagged behind, sometimes way behind. So some of those brown ducks were just getting a few green feathers on top of their heads, and it would be a while before they caught up with the rest of the males.

Most of the cottonwoods were nearly leafless (and I would soon have to clean my rain gutters), although the alders were still leafy. A little stroll through Eaglecrest meadows gave us not only some tasty alpine blueberries but a few floral surprises: we found a single blooming bunchberry flower amid thousands of others bearing ripe fruits. One late-blooming pink bog laurel flower stood out against a background of mostly green. There was even a lonely shooting star, which commonly blooms in spring. These solitary flowers had gotten their hormonal signals crossed and had no hope of pollination at that late date.

Fall is mushroom season, and they were in full exhibit out around the Eagle Beach area. Big moss clumps growing way up on the side of a cottonwood tree sported great tufts of white ‘toadstools’ (but no toads, up there). Alder stumps were covered with crowds of brown mushrooms (I fear I’m sadly ignorant about mushroom ID). Tough little bright orange fungi poked through the packed gravel on the trail. Purple coral fungi (I do know that one) were common in the forest, growing in groups of slender, pale purple ‘fingers’.

Amanitas. Photo by David Bergeson

Beautiful, but poisonous, fly amanitas (or fly agarics) spanned all age classes from bumps newly emerging from the ground to decrepit and no-longer-beautiful old age. The cap comes in various colors: often red, but sometimes orange or yellowish. The ‘fly’ part of the name may come from an Old World custom of putting pieces of this widely distributed mushroom in a dish of milk; this apparently attracts and traps flies. Despite their well-known toxicity, many of the mature amanitas had nibble marks around the edges, where squirrels or mice had snacked. Amanitas are important components of the plant community, because they form mutualistic associations with many trees, providing nutrients to their partners and sometimes serving as links for transport of nutrients and defensive compounds between trees.

There was plenty of bear sign: tracks in the mud, a few scats with undigested high-bush cranberries mixed with vegetation fibers, and numerous shallow digs. Some of these digs had turned up clumps of the white nodules of rice root (a.k.a. chocolate lily), but these remained uneaten. Instead, the bears may have been after angelica roots, but that’s a guess, because there were few identifiable remains. Small brown slugs festooned themselves over the digs, enjoying the decaying leftovers.

We found two of the small brown slugs engaged in some sort of sexual activity. They circled each other, with penises erect, for many minutes. We went off to look at something else briefly, and when we returned, they had each gone their own way. So we don’t know if they were just thinking about mating, or if they were engaged in some post-mating display, or what. Slugs are hermaphroditic, meaning both male and female (Hermes was the Greek god of travelers and the handsome messenger of Zeus; Aphrodite was the goddess of fertility and love), and mating is generally reciprocal. After mating, slugs of some species chew off their mate’s penis, but there are many kinds of slugs, and I don’t know if that curious habit applies to these. One might well speculate about how this habit came about!

As the temperatures dropped below freezing around the high mountain peaks, the water levels of our glacial rivers dropped markedly, leaving sloughs and sandbars and exposing interstadial wood from forests that grew in the valleys before the Little Ice Age glaciers demolished them. We surprised a dense gang of gulls and six or eight ravens gorging themselves on stranded salmon carcasses in a slough beside the main river. Farther upstream, a broad sand bar had hosted a wolf party that apparently involved some dancing. One of the cavorting group had left enormous tracks in the sand, some of the largest we’d ever seen. What fun!

A soggy, sorry January

A dull, dreary, soggy January! Unseasonably warm, and some bears emerged from hibernation. Many of the trails were a mess of mud and slippery roots or hard-packed ice, so ice-cleats were very useful. The lichens and mosses appeared to be very happy, however, as well as some late-fruiting fungi.

On a stroll through the forest, occasionally a small, bright orange or yellow spot attracts the eye. Looking more closely, one can see that they are fungi of jelly-like consistency, growing on dead twigs and branches. The majority of each individual fungus is comprised of long filaments (technically hyphae) that burrow through the decaying wood. The bright color is displayed by fresh spore-producing bodies that release spores when mature, but age turns the orange or yellow to dull brownish. Some species of jelly fungi occur chiefly on dead conifer branches, while others live on dead branches of deciduous woody plants. Another kind is a parasite on other fungi that contribute to the decay of woody plants, frequently growing on the hyphae of the host fungus, inside the dead wood, so it may look like the parasite is growing directly on the wood. Some of these very colorful fungi look rather like tiny golf tees. Others are lumpy blobs or convoluted ribbons, and a blobby species sometimes can look a lot like a convoluted species; two of these, in different genera, bear a common name of witch’s butter.

I thought perhaps I could learn to identify these jelly fungi in the field, at least to genus, without doing the strict mycological method of looking at the spores under a microscope. Ach, not so easy! We have several species of orange jelly fungi. Some seem to be distinguishable to genus (but not to species) even in the field, but others, particularly the witch’s butters, are more difficult. More experience needed!

In addition to the orange witch’s butters, there’s a black jelly fungus called black witch’s butter, a species of Exidia, which grows on the wood of deciduous trees. For me, this begs the question of why these fungi display these colors. Do the pigments serve some particular functions?

Thinking about the common name of these fungi made me wonder about the prevalence of witches in the common names of local organisms. In addition to the ‘butter’, we have witches’ brooms caused by parasitic mistletoe, mostly in hemlocks. And there is witches’ hair, a stringy, tangled lichen that often festoons tree branches and is eaten by deer and mountain goats. And then there are all the things associated with devils, too–devil’s club in the forest understory, and the Devil’s Paw (which fronts the ‘Hades Highway’) and Devil’s Thumb poking up out of the icefield. Hmmm, the practitioners of the black arts seem to be everywhere!

In the same vein–there is a moss called goblin’s gold, which lives in moist, dark little grottos in rocks or under rootwads of fallen trees. It is not very common here, but we found it once. It is luminescent, because special lens-shaped cells in part of the plant capture even dim light, and the adjacent chloroplasts (which contain the green photosynthetic pigment) then gleam a greenish-gold. So a little stand of this moss can, at least to some imaginations, suggest a goblin’s hoard in a small cave. It is not the leafy part of the moss that reflects the light; it is the ‘juvenile’ thread-like part (technically the protonema), which is retained when the moss matures and makes its leaves.

Early February was brightened up a bit by seeing a flock of redpolls foraging on alder cones. I usually begin to see them sometime in February or early March, as they move around from one alder stand to another. They nest in the Interior but irrupt in huge numbers about every other year, moving southward over much of North America in response to shortages of seeds in their northern nesting areas. Smaller numbers probably come to us in Southeast almost every year. They can eat lots of small seeds, such as those of alder, at a time, storing them in an expanded part of the esophagus. Later, they can regurgitate the seeds, remove the husks, and swallow the kernel. Very convenient for keeping a full tummy during the long winter nights.

Thanks to Dr. Gary Laursen, mycologist, for patient, helpful consultation.