Earth tongues

Common Earth Tongue, Geoglossum difforme

I’d just like to start by saying – the moth book is done! Done! I took it to the post office and mailed it off today, with much excitement (the clerk, whom I asked to take a photo as I pretended to put it in the mail slot, didn’t quite appreciate my excitement, I don’t think). Of course, the book’s not completely done. There’re many more steps yet to go even once the initial manuscript is prepared and finished – a fact that I didn’t truly appreciate until I was doing a book of my own. Once our editor gets the files I sent her, she still has to edit all our text, we need to make any revisions as required, then the contents go on to layout, come back to us for proofing (the trademark Peterson arrows get put in at this stage), and go back for final revisions, before ever a copy gets printed. Actually being involved in the production of a book has been rather enlightening, not least of all in the amount of time it takes to get a book from idea to store shelf. It’ll have been about four years, in our case.

So life finally returns to normal for me. For the last, oh, three months or so, I’ve been buckled down and focused on completing the moth manuscript. A lot of things have fallen by the wayside, and I’m looking forward to getting back to all those things I’ve been missing. Like the blog! I’ve had these photos since last week, fully intending to post them shortly after taking them (I’d also been expecting to wrap up the book before the Thanksgiving weekend).

Over dinner one evening last week, Dan asked if I’d noticed the interesting mushrooms growing down near our little bog/fen. I’d been down that way a couple of times in the preceding days, but hadn’t gone in too far, and hadn’t noticed any odd fungi in the part that I had traversed. He commented that they were just the other side, a whole patch of them, thin little dark things sticking up from the moss. I said I’d check them out the next time I went out. In the meantime, I brought down my field guide to fungi for him to look through and see if he recognized them.

Common Earth Tongue, Geoglossum difforme

He picked them out fairly quickly, and after going back to have a look myself I easily agreed. These are earth tongues, probably Common Earth Tongue, Geoglossum difforme, a common and widespread species. By his description I had expected them to be coral fungi, but they’re actually a type of sac fungus. It’s the same group of mushrooms that contains the highly prized truffles and morels, though the guide suggests that the majority of members are not so edible. Most fungi produce their spores individually and release them through pores or from gills; sac fungi produce their spores grouped within sacs, each sac containing several spores (the number varies by species, but the average is eight). You can see some neat images of Common Earth Tongue spore sacs under the microscope at this page here (it’s from the website of the author of the field guide I use, George Barron)

The method of dispersal also depends on the species, but earth tongues share the same general mechanism as morels. The type of fruitbody is called an apothecium, and the sacs of spores are layered on its outside surface. Immature spores are pigmentless, but mature spores develop pigment to protect them from UV while they are airborne. When the spores are mature, the sac bursts, projecting them into the air for the wind to catch and disperse. Apparently with some species, if you blow gently on the mushroom when the spores are ripe you can trigger the sacs into bursting, releasing puffs of “dust”. I didn’t try it on these ones, in part because I didn’t know to, but even if I had they were damp and tacky and probably wouldn’t have been releasing any dust anyway.

They were all growing in a small patch of sphagnum moss, a short distance from the edge of the bog/fen. From the way they were distributed it looked as though they had an association with the moss, but I suspect it more likely that the moss simply kept the ground there nicely damp compared to the surrounding dirt; there’s no mention of moss in the guide.

Common Earth Tongue, Geoglossum difforme

Advertisements

A selection of summer fungi

Yellow Nolanea - Nolanea murraii

Fall is the time when the greatest diversity of fungus (mushrooms) is usually seen, with the boldest colours and most interesting, eye-catching shapes. However, summer can be pretty good, too. We’re just starting to see quite a number of speciies appearing in the woods around our research sites, and I’ve been collecting photos for sharing here. There are quite a number of nondescript species in the woods, as well, but these are some of the more interesting ones I’ve come across recently.

The first one is Yellow Nolanea, Nolanea murraii. We found these in the deciduous woods at Rock Ridge as we were hiking out one day. Their yellow colour caught my eye at first, but it was the intriguing peaked conical caps that grabbed my interest. It’s a fairly common and widespread species, also sometimes called Yellow Unicorn Entoloma. Entoloma is an alternative genus – I gather that taxonomy for this group of mushrooms is still being sorted out.

Yellow Waxcap - Hygrocybe flavescens

Another yellow one, this is Yellow Waxcap, Hygrocybe flavescens… I think. You’d be surprised at how many bright yellow, small, flat-capped, gilled mushrooms there are. One of the characteristic features of waxcaps are, unsurprisingly, their shiny, waxy caps, and this one certainly has a shiny cap.

Gilled mushrooms such as this one are usually separated by the colour of the spore print they make. A spore print is when you take the cap of the mushroom off the stem and set it on a piece of paper for an hour or two. The spores fall out of the gills and onto the paper, leaving a print. Depending on the species, the print may be pinkish, brownish, or light or dark colours (usually variations on grayish). Yellow Waxcap is in the light-spored group, and has a whiteish spore print. Of course, I don’t really like to pluck the cap off mushrooms I find, particularly if there aren’t very many of them, so I’m content to call the species a “maybe” and leave it at that.

Conic Waxcap - Hygrocybe conica

I believe this is another member of the same genus, Conic Waxcap, Hygrocybe conica. The yellowish stems and shiny orange caps seem to match (Conic starts out red, but fades to orange as it ages). The downside of taking photos and trying to ID from them later is that often you don’t know to check for certain features. For instance, Conic Waxcap, when you bruise it, turns black. I didn’t think to try bruising it, so I don’t know if this mushroom would turn black or not.

Orange Bolete - Leccinum aurantiacum

This one was clearly a bolete. Boletes have solid undersides with many small pores from which they release their spores, rather than the gills of the first three mushrooms. Narrowing down the species of bolete is trickier. I think it’s Orange Bolete, Leccinum aurantiacum. The guide book specifies the spore print to be brownish, but again, I didn’t try doing that. It was the only one in the area that I noticed. The stalk is supposed to have red-brown or black dots, but the photo in the book doesn’t show dots, or at least nothing obvious.

Marasmius delectans

This dainty little species was growing in the path at Rock Ridge on our last visit, having popped up in the week and a half since we were previously there. There are a couple of genera that are characterized by small caps on delicate stalks. One is Mycena, and the other is Marasmius. This one is Marasmius delectans, I think (noticing a pattern with that word?). Most of the species have whiteish caps with darkish stalks. Many are told apart through variations in the shape and size of the cap, and can sometimes be subtle.

Earth Fan - Thelephora terrestris maybe and Marasmius androsaceus

This frilly brown fungus, resembling a spruce tree a bit in its structure, caught my eye as I was checking out a family of Field Sparrows foraging under some pine trees at Rock Ridge. I think it’s a species of Thelephora, possibly Thelephora terrestris, Earth Fan. My book suggests it should have a whiteish margin, but there are some photos online that don’t show that.

As I was editing the photo, I noticed that there were little Marasmius mushrooms growing alongside it that I’d completely missed when I was there in person, as caught up with the main fungus as I was. These ones seem to have a brownish centre to their cap and I think they may be M. androsaceus.

Golden Coral - Ramaria aurea

And finally, this fungus I discovered when I stepped off the path to photograph a group of Indian Pipe at Maplewood Bog a couple weeks ago. Appropriately, fungi that grow in branching formations like this are called coral fungi. I suspect this one is Golden Coral, Ramaria aurea. One of the notes in the guide is that the species has a thick, short, whitish stalk, which this one has. The fungi shown above all release their spores from either gills or pores on their undersides, but coral fungi are covered with a layer of spore-producing cells that are essentially their skin.

Fungal growths

Amanita muscaria - Fly Agaric

So, the long-awaited post on fungi. As I mentioned a few days ago, while out hiking the woods on our numerous excursions to the park I encountered quite a number of interesting fungus species. I dutifully took photos of everything, making sure I got a nice clear photo (as best as I could, anyway, given the low light conditions), checked the underside when I remembered to, and then came home to try to identify them.

It didn’t take me long to realize just how unhelpful a photo can be for many mushroom species. There are several that are very distinct and easy to recognize, of course, such as the above. The bright colour of the cap, covered in white spots, makes it an Amanita sp., but how to tell Amanita muscaria from Amanita flavoconia? I think this is the former, also known as Fly Agaric, which is supposed to be very common. There are different colour varieties, yellow, orange-red and bright red, with the latter being absent around the Great Lakes, but common in the west. A few species of Amanita are edible, but this brightly coloured one is poisonous. They contain amatoxins, a group that can destroy liver and kidney function in even the tiniest quantities, resulting in a relatively quick and painful death.

Scleroderma areolatum, maybe?

If I’m correct in my ID, this is another poisonous mushroom, Scleroderma sp., probably S. areolatum. This large, globular puffball was found growing on a ravine slope. The puffballs, at least the mushrooms I think of as puffballs, are spherical masses, lacking a stem and growing right on the ground. Growing up, there were Giant Puffballs in the woods behind my parents’ house, but I haven’t seen them for years. I thought they were the coolest things. I’m not sure if they get their name because they’re all puffed up and swollen, or because when you poke them (or they’re hit by falling raindrops, twigs, or other items) they release a big puff of spores, but either way, they’re unusual.

Lycoperdon pyriforme - Pear-shaped Puffball

There are actually edible puffballs, and this is one of them (as is the Giant Puffball). Although much tinier than the previous species, no more than an inch or two, they function in much the same manner to release their spores, except that there is a pore at the top that the spores are released through. This species is Pear-shaped Puffball, Lycoperdon pyriforme. According to the Lone Pine field guide, this is the most common puffball species in the northeast, though this is the first time I’ve encountered it. It characteristically fruits in dense clusters on rotting wood; the ones I found were at the base of a tree, so I wonder what that says about the tree. The guide notes, “Edible, but lacks flavour.”

Suillus americanus - White Pine Bolete

I believe these are White Pine Boletes, Suillus americanus. The boletes are a group halfway between the stalked, gilled mushrooms and the pored bracket fungi – they have a stalk and cap but have pores like bracket fungi. As the name suggests, this species is usually found fruiting in the soil under White Pines. There were certainly a few of them in the area, though I can’t recall now if I specifically found this one at the foot of a White Pine or not. It’s listed as edible.

Russula paludosa

My best guess on this one is that it’s Russula paludosa. This is where I realized how much easier it would be to identify these mushrooms in the field, with the book in hand, or otherwise by bringing a sample back. First, I’m not completely certain about the underside, though I think it’s gilled. Second, the genus Russula has the characteristic of brittle gills, instead of the spongey texture I tend to associate with mushrooms. It’s hard to run your finger along the gills in a photo to see if they break, though. I suppose part of my problem is that I don’t like the idea of breaking or picking something unnecessarily, so if I can check the underside without doing so I will, and if I can’t then I don’t tend to check. The cap on this one has been munched on by something, which didn’t help with trying to narrow down an ID, either. This species is supposed to be widespread and common, though, usually in moist soil under conifers, which would fit the bill.

Clitocybe gibba - Funnel Clitocybe, and Hygrocybe miniata - Vermilion Waxcap

Two species in this photo, both tricky to identify without the specimens in hand, but I think they’re Funnel Clitocybe, Clitocybe gibba, and Vermilion Waxcap, Hygrocybe miniata. A lot of narrowing down the potential species for a mushroom depends on the colour of the spores, which is generally determined by taking the mushroom cap, sitting it on a piece of white paper for a few hours to allow some of the spores to be released and fall onto the paper, and then looking at the “spore print” that’s left when you pick the cap up again. Since I don’t have that luxury, I do the best I can with visual IDs and comparing habitat info. I’m fairly certain about the waxcap, but the clitocybe (or whatever it is) could easily be misidentified. Both species are listed as fairly common, so I figure my chances are good…

Marasmius capillaris

This one, Marasmius capillaris, was a slightly easier identification because of the daintiness of the mushrooms. There are really only two groups that produce such tiny caps on thin, delicate stems: Marasmius sp. and Mycena sp. (the latter of which I mentioned back in the winter). The ID for this species was aided by the fact that there was a photo in the Lone Pine book that almost exactly resembled my photo, right down to the leaf litter the mushrooms were growing out of. Also widspread and relatively common, it apparently comes up quickly in periods of extended rain, but will shrivel quickly so is often missed.

Hericium sp, maybe?

And finally, what I thought would be the easiest ID but turned out not to be. This is obviously a tooth fungus of some sort, much like the Shelving Tooth of this post, but growing in a clump instead of as a stalked mushroom or bracket. Easy, right? There’s only a few such species listed in the book. However, none of them seemed to match quite right. I’m thinking it’s maybe not shown, but could be a member of the genus Hericium. These fruit in clumps on the sides of logs or snags, and both the ones listed in the guide are indicated to be widespread and fairly common. Also edible, though I’m not sure how you’d fry this one up.

Edit: Jennifer (see below) just wrote about Hericium; based on her post I think this might be H. erinaceus.

For more neat fungi check out the stuff Jennifer of A Passion for Nature found on a walk back in August. Perhaps I just wasn’t paying close enough attention, but I sure haven’t seen anything that colourful around here!

Fuzzy fungus

Schizophyllum commune, split gill fungus

I discovered this neat little fungus growing on some beaver-downed logs at the research station earlier this week. It was unusual in that it was fuzzy, and it caught my eye because of the attractive lobing of the growths into neat leafy shapes. I went back once the sun was high enough to peek over the trees and took a few photos.

Unfortunately, the field guide I had used to identify the fungi back in January had been a library book, so I didn’t have it on hand. And trying to find the identity of something is much aided by a field guide like that. There aren’t any good, complete references online (or at least, if there is one I didn’t stumble across it in my searching). However, I finally discovered something that closely resembled my fungi while browsing search results from ForestryImages.org.

Sure enough, further investigation reveals it to be Schizophyllum commune, or the split gill fungus. The genus name literally means “split leaf”. And naturally, the key identifying feature of this fungus, the split gills, I had no photo of. I had peeked under the cap to check out whether it was gilled or pored, determined that it was gilled, and left it at that. Who knew it was that important?

Schizophyllum commune, split gill fungus

I actually do have an image of the split gills, above. This is a crop-down from one of the larger photos, which just happened to have one individual curling up enough to expose its underside to the camera, which was nearly overhead. It actually looks more like paired gills, rather than split, with the ridges radiating in twos out from the centre. Schizophyllum is the only genus with this characteristic, and is in fact so unique it has its own family, Schizophyllaceae.

Schizophyllum commune, split gill fungus

There’s a handful of species in this genus, but Schizophyllum commune is by far the most common. It’s found across North America, and in fact occurs on every continent except Antarctica, where there’s no wood for it to grow on. It superficially resembles the commonly-found bracket fungi that grow on trunks and logs, but has these “gills” instead of pores. The gills aren’t actually spore producing the way they are in true gilled mushrooms, but are instead simply folds of tissue.

Similar to the Mycena corticola I posted about in January, these fungi are marcescent: they can dry out over the winter months or during periods of low moisture, and then come back to life at the next rains. This adaptation is part of what makes this fungus so successful around the world. Rather than growing new fruiting bodies each year, the fungus’ “roots” (the mycelium) only have to produce one growth which will last throughout the year, even during dry spells.

Schizophyllum commune, split gill fungus

Fungus reproduction is a complex thing, where compatibility of external mating structures is less important than compatibility of genomes. In order to reduce the likelihood of inbreeding, a fungus can only “mate” with other fungi that have a different DNA sequence (allele) at a gene location (locus) from their own. To compare to humans, it’s like blue-eyed people only being able to mate with brown-, green-, or hazel-eyed people, but not other blue-eyed people. In fungi, there’s usually two loci used in mating compatibility, and each locus has multiple alleles. In the case of Schizophyllum commune, there’s more than 300 alleles at the first locus, and over 90 at the second – resulting in more than 28,000 allele combinations. So instead of the two sexes found in vertebrates (male and female), there’s 28,000 sexes in this species of fungus! This enormous number means any given individual will be compatible with over 99% of the rest of the population (vertebrates are only compatible with 50%).

Schizophyllum commune, split gill fungus

One other wild thing about this fungus – it doesn’t just stick to rotten logs. There have been a number of reports (though very rare) of the spores of this fungus (presumably inhaled) infecting the respiratory tract of humans. For instance, this poor woman had the fungus actually growing in her sinus cavity! Of course, it probably didn’t have these lovely fan shapes inside her nose, and it was identified using DNA sequencing. In another, the fungus had grown through the soft palate of a child and was forming fruiting bodies in her sinus. I can’t find the actual paper on that one to determine whether they were actual mushroom-shapes, though all the sites that mention it sure make it sound that way (this site is where I read it first). Others document lung, airway, and even brain infections.

So be careful not to inhale too deeply when you bend over to check this neat little fungus out…

The Black Knot

Edit: This post was recently included in the March edition of the Festival of Trees, a blog carnival focusing on, you guessed it, trees. You can check out the full edition at Orchards Forever.

Black Knot

There is a bush in the backyard, behind the house, growing beside a large stump. The stump is what remains of a mature pine that came down before I was around, struck by lightning. The shrub and stump were a play-spot for my sisters and I when we were young, and I remember picking blackcaps from the canes that grew under its branches.

In recent winters I’ve noticed a few black, crusty growths forming on some of the small branches. It’s a familiar phenomenon, but one I hadn’t investigated before. When I was much younger we had a plum and a cherry tree on the property, and I recall plucking ripe plums from the branches of the one, and my parents complaining (good-naturedly) about the birds eating the fruit from the other. Both gradually succumbed to a crusty black fungus, and while the cherry struggles on, the plum long ago died and came down (although I did notice a hopeful new sapling right beside where it used to be).

So to see these growths forming on another tree I knew as a kid, I thought I’d investigate. Turns out, it’s fairly common. It’s a fungus, Apiosporina morbosum, known by the common name “the Black Knot” (which sounds rather dramatic). It almost exclusively infects trees of the genus Prunus, which includes cultivated species such as plum or cherry, or wild native species such as chokecherry or black cherry. The little shrub in the backyard is a chokecherry.

Black Knot

This little tree, although I didn’t try to identify it, is probably a black cherry, the most common Prunus species in these woods. It has a substantially more progressed infection. The fungal spores infect the young buds of the tree when it’s just leafing out in the spring, and it takes a few months for the infection to appear. Initially just look like thick brown galls. Eventually, the following spring or summer, the bark splits and the gall turns into these charcoal-black, crusty growths.

The fungal growths are most often seen on smaller branches, but like in the above photo, can sometimes spread to the trunk of the tree. Although an infection on a branch can compromise the branch’s growth and create disfiguring contortions (such as the first photo), it only kills the branch if the growth completely encircles it (called “girdling”). Any portion of the branch above the fungus will die. If the fungus girdles the trunk of the tree, the whole tree will die. The fungus will continue to spread over many years, and eventually will either compromise the tree so severely it will die, or girdles the trunk causing death.

The fungal spores are released by splashing rain and carried by the wind, and mild spells during the spring rains trigger their production and release. Once a tree’s infected, an individual growth will only live a couple years (after which it dies and turns whiteish-pink, colonized by another species of fungus), but during that time it has the ability to spread to other areas of the tree.

The good news is, you can do something about it if one of the trees in your yard becomes infected. It’s simply a matter of removing the infected bit, cutting back to 10 or 20 cm below the infected bit (since the fungus travels under the bark and may be present outside of the growth). This is best done in the winter while the tree and fungus are both dormant, and the fungus should be burned or otherwise disposed of so it doesn’t infect other trees.

So there’s some hope for the little shrub, and perhaps if I prune it this winter I can keep it from spreading to the mature chokecherry that shades the kitchen window. Now just to dig the gardening shears out from where they’ve been packed away for the winter…

Fungi of the winter woods

Fungus4

So back to those itty-bitty mushrooms. The tree was actually the first one my mom and I had stopped to examine the lichen on, and it was fairly unremarkable for the most part. There were little patches of blue-gray foliose lichen up and down the trunk in the first five or six feet from the ground, but nothing that really stood out and grabbed my eye. If this had been the second tree we looked at, after examining the Sugar Maple for instance, I may not have given it more than a cursory glance. It was just by chance that the photographs I took of the lichen on this tree happened to be near a deep crevice in the bark. And at the back of this crevice, with small numbers climbing out and onto the surrounding bark, were these teensy-tiny mushrooms. To give you a better idea of scale, let me post a picture with a reference piece:

Fungus13

That’s a normal HB pencil. Identifying these little guys was a bit of a challenge. The Lone Pine field guide to Mushrooms of Ontario and Eastern Canada is an excellent reference in terms of providing good colour photos and info on the different species, but it contains 609 species of mushroom and fungus, and these are only just a selection of the most common species likely to be encountered. I couldn’t find a species in the book small enough to be this one, but I narrowed it down to a couple of likely genera, and then did a Google search. I’m reasonably certain the species is Mycena corticola, also called “Bark Mycena” because it grows exclusively on bark, usually freshly fallen or declining living trees. Unlike many mushrooms that grow on live trees, this one doesn’t damage its host, as it doesn’t reach deep enough into the tree to affect the tree’s food transportation system. It’s often found in association with lichen or moss, such as it is here. It is “marcescent”, meaning it has the ability to dry up when moisture is low, and come “back to life” after precipitation or fog. I took the second photo, with the pencil, today and the first photo yesterday, and you can even detect between the two a bit of drying – the mushrooms in the second photo are browner and look a little shrivelled in comparison; I had some difficulty finding a good patch to take the photo of. This may also be in part due to age – they probably came out during the warm spell last week, and the purpleish colour eventually fades to brown as they age.

Fungus10

Mushrooms are hard to find at this time of year since most of them don’t grow under layers of snow. Fungus, however, is easier to come by. Undoubtedly the easiest to locate in the winter are those large fungal growths that you usually find secured to the side of a rotting stump or log. They’re called “bracket fungus”, or sometimes “polypores” because they have many (“poly”) tiny pores on the underside of the growth to release reproductive spores, instead of the “gills” we associate with mushrooms (what you see when you flip a mushroom over and look at the underside of its cap). I believe the above photo is of Fomes fomentarius, a common and widespread bracket fungus. Its common name is “Tinder Polypore”, after its historical use as tinder for starting fires. If hammered flat it’ll smolder for a long time without much heat, and before matches were invented was often used to transport fire (for instance in nomad societies; in fact, “The Iceman” had a piece of it, along with some flint, in a pouch he was carrying). It was also used as a primitive medical tool and has been shown to contain certain substances, such as iodine, that prevent bacterial growth. It grows commonly on birches, and indeed all the ones I found in the woods were on birch.

Fungus11

This is another type of bracket fungus, I suspect Cerrena unicolor. One of the frequently mentioned identification features is that C. unicolor is whiteish or brownish in colour but is frequently greenish due to a layer of algae growing on top, which is clearly the case here. This species has an amazing relationship with a couple of wasps, the horntail wasp (genus Tremex) and ichneumonid wasp (genus Megarhyssa). The horntail wasp female carries around spores of C. unicolor in her ovipositor, and when she lays her eggs in the bark of a tree, the spores are deposited with it. The spores begin growing into the bracket fungi in the photo, and in doing so create a large network of fungal “roots” (called “mycelium”), which the horntail larvae feed on during their development. When the larvae pupate, they absorb some of the spores into the pupa, which are then incorporated into the female wasp’s ovipositor during development to allow the cycle to continue. Now, I don’t exactly understand why the fungus does this next part, but perhaps it’s to keep the larvae from eating it out of house and home (the mycelium are its connection to its food source, after all). The fungus will produce a pheromone that attracts ichneumonid wasp females, who come and lay their own eggs. When the eggs hatch, the larvae parasitize the horntail larvae. Whoda thunk all that was quietly going on under those fungal growths?

Fungus14

 Edit: It’s been suggested to me that this is actually a gypsy moth egg mass, and after looking it up, I think that’s correct. This is one pitfall of identifying something yourself, particularly in an area that’s new to you (like fungi). The description in the fungus field guide was a pretty good match, and the image, although small and difficult to discern details, sure looked like it. Perhaps this is the moths’ camoflauge technique? :) In any case, I’ll leave the text as is, for the information on slime moulds (which should be correct regardless of the identity of the above).

Here’s one last fungus to close off this post. I just happened to spot this blob of creamy brown on the trunk of a tree as I was leaving the forest yesterday. At first glance it looks like someone thwacked the bark with a wet fluffy cattail head, or it might be something a cat threw up (though getting it five feet up a tree would be a feat even for an ambitious cat). It actually belongs to a group of fungi called “slime moulds”, which are fungi that lack the defined shapes we tend to associate with the group. Similar to the fungi that grows on the forgotten leftovers in the back of the fridge, it’s often (though not always) a large blob of roughly uniformly-coloured stuff (for lack of a better word).I’m not sure of the particular species of the above specimen, but there are only some 500-odd species in the world, most of which are very widespread, indicating that, evolutionary speaking, they’re all very old. They have two life stages. The above is the “fruiting” stage, where they produce spores to carry on the next generation. Their first life stage is as a “plasmodium”, a slime (from which they take their name) that is not often seen as it usually resides in rotting logs or other decaying matter. When it comes time to spread their seed, however, they need to move to a better location where the spores can be caught by the wind or otherwise dispersed. The crazy thing is – they move like amoebas, crawling across surfaces to find a good fruiting location, ingesting organic particles in their path and ejecting ones they can’t eat. All at a rate that would make a snail look like a cheetah, however! As a result, they don’t move far, usually just a couple metres at most. And I’ll leave you with this food for thought: slime mould has recently been shown to be able to navigate a maze, connecting two points through the shortest possible distance to food – perhaps an example of primitive intelligence in a fungus?

Winter colours

Fungus1

Winter is a time of year that most people tend to think of as very monochromatic – whites and grays, perhaps a bit of blue, and maybe some green from the conifers. And, on the landscape scale, this is probably reasonably accurate. However, when you start poking around, you can turn up some fabulous colours. My mom suggested this as a topic for a post, and so we went out this afternoon to do some hunting.

This photo was taken from the Sugar Maple in my parents’ front yard. It’s an old tree, in the twilight of its life. When I was a kid we had a swing made from a tire hanging from one of its sturdy branches, and a treefort high in the fork of its trunk. It was a healthy tree then, without any blemishes or disease. Since then I’ve watched as some branches have died, leaving gaps in its crown that look like somebody’s taken a quick bite for a midnight snack. The bark started flaking in some spots, and the branch with the swing is long gone. And, perhaps the most obvious sign of a tree in decline, its trunk started blossoming in richly-coloured flora.

Fungus2

Well, not flora, exactly. The growth is actually lichen, which isn’t technically a plant. In fact, it’s not easily classified, because it’s not a single organism, it’s two – a fungus (which is its own type of organism) and an algae (which is a completely different type of organism), partnered together in a symbiotic relationship that benefits both. Although technically the fungus and the algae could live independently, they find it suits them both, especially in harsh or difficult conditions, to partner up so each only has to do half the work. The algae contributes to the partnership by photosynthesizing sugars, much like trees do. It’s the algae that gives lichen its green or blue-green (or sometimes red or brown, depending on the particular type of algae) colour. The fungus, meanwhile, is the house the algae lives in, and it pulls in minerals and nutrients necessary for the pair’s survival.

Fungus5

There are over 25,000 species of lichen in North America alone. Each species is incredibly well-adapted to a particular niche, and they can coexist easily, as you can see in the above photos. Because of the vast number of species, and the superficial similarity of them all to a human eye, I’m not even going to try to classify any of these to any sort of taxonomic level. It is possible, however, to group them into structural categories. In the above photo, the lime green lichen is considered “crustose lichen” – it’s very short and relatively uniform. The blue-gray lichen is a “foliose lichen”, which tend to be as the name suggests – leafy and broader. A third, which does not appear on this tree but is often seen, is “fruticose lichen” – a three-dimensional lichen that resembles tiny branches or shrubs.

Lichen is incredibly hardy, withstanding temperatures and conditions that would see most other plants perish. It can be found in the deserts where temperatures can reach up to 50oC, or in the arctic where it may drop to -50oC. Because of their low profile, they can grow in windy environments that don’t support tall plant life. They can also survive in areas without much soil, because the fungus secretes an acid that roughens the substrate surface (such as a rock face) to allow the attachment of its root-like tendrils. If anywhere epitomizes harsh conditions, it’s Antarctica, and there are over 350 species identified from this continent alone!

Fungus6

They take most of their nutrients and moisture directly from the air. Because of this, lichens are especially sensitive to air pollution. It’s been observed that the more pollution in the air, the fewer species of lichen in an area, to the point where in the city centre there’s practically nothing. In London, England, at the start of the industrial revolution, there was so much pollution in the air from coal-fired plants that the lichen on trees in the city completely died, leaving blackened, soot-covered trunks. A moth that was patterned to camoflauge against the trunk suddenly became very obvious to predators. However, an uncommon dark morph blended in well with the new lichen-free trees, and within a short time nearly all of the moth population were dark. When the air was eventually cleaned up lichen returned to the trees, and the moth reverted to its peppered form. Lichen tends to grow very slowly, at about 1mm per year. Some especially dense patches can be dozens, if not hundreds of years old.

Fungus3

Another old tree in the front yard is a Silver Maple. Although we never played on this tree, it, and its sister a few yards away, have framed the front of the house for decades, and certainly it’s a fixture that I can’t imagine the house without. It must be almost as old as the Sugar Maple, and although it’s retained all of its major branches, the lawn is always littered with small- and medium-sized ones in the spring or after a good storm. Sure enough, when I investigated it had its own patch of lichen along a lot of its lower trunk. There weren’t as many varieties as on the Sugar Maple, I only really noticed two, and one was the same blue-gray type. However, after running off a few shots I peered closer and discovered really, really tiny mushrooms, only 2 or 3mm across, growing amongst the lichen patches!

But that’s a topic for another post. :)