lichen

Tree beards

Not far from the tree with the beetle engravings I discovered one with a tiny poof of lichen. Just the one, on a small tree that could even have been a long-dead sapling; there were no others near it, or even in the immediate area, that I could spot. I found this curious. At first I thought it was perhaps a reindeer lichen that had been picked up and dropped there by some animal, but when I picked it up it seemed to have grown around the twig, with a distinct groove down the centre. I ran off several shots, but lichens are a tough bunch to decipher, and I didn’t really know for sure what I was looking at.

I carried on up the trail, and a short distance later came upon some thick fruit-bearing trees, perhaps crabapples. I’d walked by these trees dozens of times before, and never noticed anything remarkable. But for whatever reason, that day something caught my eye: fuzzy patches of green lichen growing from their trunks. Whereas there’d just been the one on that first little tree, here there were dozens. None of them were very big, even the largest was not much larger than a tennis ball. Most were only half that size. They were very delicate and fine, almost hairlike. I had more of a suspicion as to the identity of these, but it would require returning home to ask the internet (my god is named Google; Google will provide).

I am fairly certain that these are Usnea sp., also known as Old Man’s Beard (which may refer to one of many species of Usnea lichen), or at the very least the latter bunch on the crabapples are. I’m not completely sure about the first one, I would probably need to go back to check out additional characteristics. Usnea lichens typically grow from the branches or trunks of trees, and are always fruticose – that is, highly branching. Some species grow more thickly than others, and some have broad flat bits that remind me a bit of opened venus fly trap jaws. There are a number of species that grow in Ontario, but I think this one might be Usnea subfloridana, a particularly filamentous species but one that doesn’t typically grow very large or long. Some species can grow very long, a foot or more, and completely cloak the branches of a tree.

All lichens are susceptible to air pollution, but Usnea lichens are especially so. They’re one of the first types of lichen to disappear with air pollution. Even when they persist, they may not grow more than a few millimeters. Their presence here is likely an indication of reasonably clear air quality.

When I think of Usnea, I typically think of Northern Parula warblers. Parulas are almost entirely dependent on long, draping species of Usnea for their nests. They don’t just use the lichen in the nest, the lichen is the nest. They’ll find a nice thick clump of the stuff and hollow out the inside. They don’t even always line it. Because the sort of Usnea the parula prefers mostly occurs in the coniferous forests of the Canadian Sheild, the bird is rare in southern Ontario. We’re right at the edge of the Shield here, but I don’t think these little puffs are going to cut it.

Most Usnea lichens, along with a few others such as reindeer lichen, contain usnic acid, a bitter-tasting molecule believed to be used to deter animals that might browse on the lichen (apparently it doesn’t deter the reindeer). It also happens to be a very potent antibiotic and antifungal agent, and is high in vitamin C. These latter properties resulted in it being a common medicinal agent used by Native Americans to treat infections – both internally, as a tea, and externally, as a compress on wounds. The fine, branching nature of the lichen also made it a good substitute for gauze. In modern day herbal medicine it is often used in teas or other products intended to treat respiratory and urinary tract infections.

All good things to know if I find myself lost and sick in the northern woods…

Winterizing the brain

It’s that time of year, the transition between summer abundance and winter dearth. In the warm months it’s so easy to find something to blog about: life is everywhere. Insects, flowers, birds, green leaves everywhere you turn. The brain gets lazy, there’s no need for it to work overhard. Then come October and November, all that great wealth of life begins to thin out. You go out with your camera to find something to blog about and the brain says, “Are you kidding me? There’s nothing out here!” It’s wrong, of course; there’s still plenty of interesting things going on, stuff to find, but the brain is in summer mode. It will take some effort and time to retrain it into a winter way of thinking and seeing.

Earlier this week I took my brain for a walk into our back fields. It saw nothing, so I made it look closer. “Let’s start with this rock,” I said, “and we’ll go from there.” My brain peered at the rock and saw only rock and moss. I chastised it. “No, look closer. Pay attention. What do you see?”

“Well, those red things are pretty obvious,” Brain said.
“Good!” I applauded. “That’s a great start. British Soldier Lichen, their red caps in full bloom, to produce spores. What else is there?”

“Um. Some spikey mosses. Lots of them there.”
“Yes! Juniper Haircap Moss, Polytrichum juniperinum,” I enthused, including the italics. “Cosmopolitan, occurs on every continent, including Antarctica! It gets reddish ‘flowers’ on the tips when it’s reproducing. You’re doing good! Keep going, what else?”

“Some branchy lichen to the side,” Brain pointed out. “Wait, I think I remember these – reindeer lichen?”
“Excellent! Yes, reindeer lichen, specifically Cladina rangiferina, which can be told apart from Yellow-green Lichen, Cladina mitis, by its blue-gray colour. It’s soft and spongy after a rain, but brittle and crumbles when dry. It’s a major food source of reindeer, hence the name.”

“There’s that curly grass stuff in the little patch there,” Brain said, warming up to the challenge.
“Probably the same stuff we walked through to get here,” I agreed. “Poverty Oatgrass, Danthonia spicata, widespread across most of the continent. It can be identified by the curly tuft of grass at its base. Grows on thin rocky soil and is very resistant to drought, probably why it’s growing in amongst all these mosses and lichens on the rock.”

“Hm. Oh, look! Cup lichen, tucked in beside the British Soldiers.”
“So there is, good eye,” I said. “Cladonia species, perhaps False Pixie Cup, C. chlorophaea, which grows on rocks, among other substrates, and is commonly found with mosses.”

“And the moss has put out spore spikes,” Brain said, now getting up to speed.
“Ah yes, just on the right. Now you’re on a roll. I didn’t even see those till you pointed them out.”

“Some dead cedar leaves, from the cedars at the edge of the rocks, I guess.”
“Seems probable. Deposited here by wind or animal, do you think?” I wondered aloud.

“Look at that cute little plant,” Brain pointed to some red leaves. “So small. Any idea?”
“None whatsoever,” I admitted. “Too bad it doesn’t have any flower heads or seed pods to help. Something to look for next summer, I guess.”

“Oh, and look. It was visited by a rabbit,” Brain finished up by pointed out one final item.
“Eastern Cottontail or Snowshoe Hare?” I joked.
Brain and I stood up from where we’d been stooped over our one-foot-square of rock.
“See? That wasn’t so bad,” I said. “All it needs is a bit of practice to get you back in shape.”
“Yeah, I guess,” Brain said grudgingly.
“You did good. Let’s leave the lesson there for now. We’ll try again later this week, perhaps.”

Today not at Kingsford – British Soldiers

It seems I often find myself at my computer late at night, just starting to compose a blog post long after a reasonable person would have gone to bed. Part of this is due to not having to be up at a set time in the morning (for instance, to go in to the office), so I don’t feel the pressure to keep to a strict schedule in the evenings. The other part of it is that some cosmic process conspires to prevent me from starting any earlier. I went back up to Ottawa to take my sister to sign the paperwork for that car, and through one thing and another ended up leaving the city later than intended. And on the way home, it started snowing. Hard. Such that I was reduced to half the speed I would ordinarily drive on a clear night (it didn’t seem to phaze the locals, however, who breezed by me in their sporty Mazdas and hefty F150s. Part of me hoped they’d get home safely, but the other part of me hoped for the gratification of seeing their taillights in the ditch a few miles up the road). When I got home the one show I watch every week was just starting, and then my Mom called not too long after that. And, well, time just slowly slips away. So all that is a very long-winded way of saying that I had planned a longer post for today, but will delay it in favour of a shorter Today post (would you believe that my university professors criticized me of being too succinct in my term papers?).

Today’s subject is British Soldier lichen, Cladonia cristatella. My sister spotted this patch growing on a stump to the side of the trail. A week or two ago I wrote about Pixie Cup lichen that I found while hiking with Dan and Raven in Frontenac Provincial Park. While looking up the ID for the Pixie Cups, I ran across a few mentions of British Soldier lichen, a member of the same genus as and therefore closely related to the Pixie Cups. It has very distinctive bright red caps, thought to resemble the caps of the British soldiers during the American Revolutionary War in the late 1700s. It’s a relatively common lichen, so it’s somewhat funny that I hadn’t run across it before, especially since you would think the bright red caps would draw one’s attention. However, at least I already knew what they were when we found this patch.

Because lichen are a symbiosis of a fungus and an alga, the red caps are actually the fungus’ fruiting structure. The structure is similar to those employed morels and some other mushrooms, although they aren’t related. It takes a lichen anywhere from 4-8 years to reach sexual maturity and begin to reproduce, so up to that point the British Soldiers would remain capless. While the ones down here may not grow quite so old, lichens growing in the tundra of the far north can reach incredible ages, some anywhere from 1000 to 4500 years. They can survive this long because they are drought-resistant (the tundra is technically a desert, after all) and very hardy. Consider that the oldest of these may have started growing back when the Great Pyramids of Egypt were being constructed, and that really puts that 4500 in perspective. Generally, though, the lichens that grow in our temperate part of the world tend to have the same sort of lifespans as the trees in the forests.

Today at Kingsford

I’ve decided to start a regular series on the blog called “Today at Kingsford” (the name of our little lake). It’s been something I’ve toyed with from time to time in the past, and I’d been giving more serious thought to since moving here. Our current location provides me with more material than I can possibly post about, particularly the sort of long, researched posts that tend to accompany most of my photos (a “problem” I didn’t have when I was living in the city). Beyond that, there are many neat things here that it would be difficult to make a full-length post about, but I would still like to share. This will be that forum.

Today’s photo is a good example of that. It started raining yesterday evening, and through the night. When I got up this morning, early, with the intention of going out to do some birding (thinking perhaps the scattered showers through the night may have downed some migrants, or otherwise kept yesterday’s from leaving), it was pouring. Wet, wet, wet. I wasn’t going anywhere. So instead I rolled over for another hour of sleep.

When I did finally get out of bed, and looked out the bedroom window at the trees and forest, the rich colours of the lichen on this tree trunk jumped out at me. I find lichen that can really blend in with a tree on an ordinary day looks beautifully vibrant after a rain, with the darkened rain-soaked bark providing strong contrast to the brilliant pale greens and blues.

Now, I wasn’t about to make a whole post on lichen in the rain, and a photo such as that would just languish on my hard drive, perhaps popping up once in a while on my screen saver slideshow. My hope is that these short posts will be “filler”, for the days in between the longer posts. There will still be days I don’t post anything at all, but while I don’t have the time to do a full-length post every day, I should have time most days to at least put up a photo and paragraph of explanation.

Winter colours

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.

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.

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!

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.

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. :)