Yellow slime mould

Eggshell Slime Mould, Leocarpus fragilis

I have spent quite a bit of time flipping through my field guide to fungi over the last couple of years. Having only a very basic understanding of mushroom taxonomy, I generally check every single page in the guide until I find a good match, especially when it’s less clear to me which group a particular individual is likely to fall into. Anyone who has spent much time browsing field guides can likely relate when I say that after a while you start to pick out recognizable species that you haven’t yet seen but would really like to. That species (or in this case, group of species) for me in the fungi field guide was slime moulds. It even made #7 on my sixth top-ten list that I posted at the beginning of the year (list #6 was of non-bird observation targets).

To say I was delighted, then, when I came across this sight on the forest floor at our Maplewood Bog site is an understatement. I was totally stoked, completely thrilled, stoked to my earlobes. And yes, over a fungus. But it wasn’t just any fungus, it was a slime mould! Number seven on my top-ten-to-see list! And I could even remember the exact photo depicting this species in my field guide, since it was probably the species of slime mould that intrigued me the most. I didn’t share my elation with Dan, though – he’s always very supportive, but I had a feeling the reaction I’d get would primarily be one of bemusement. Probably not that many people would get too excited over a slime mould. Call me a nerd.

Eggshell Slime Mould, Leocarpus fragilis

This species is Leocarpus fragilis, which goes by many common names including Eggshell Slime Mould, Insect-egg Slime Mould, and Fragile Yellow Slime Mould. The drop-shaped yellow things are the fruiting bodies of the slime mould, and the whitish stuff is the main “body”, the equivalent of the mycelium “root” network in a traditional mushroom. The difference is that the “roots” of slime moulds can get up and move. And I don’t just mean grow – I mean the whole entity can move from one location to another, climb up and over things, etc. Scientists have actually shown that slime moulds have the ability to “solve” mazes through a trial-and-error process of sending out feelers till they find the right destination, then retracting all the wrong ones and just moving down the correct one. Strictly speaking, slime moulds aren’t even fungi (though they were once classified there) – this and other unique characteristics have awarded them their own Phylum (the same taxonomic level as our classification as Chordata – the vertebrates), Mycetozoa.

L. fragilis is typically found in woodland environments, where it fruits on a wide variety of substrates including, but not limited to, twigs, dead leaves, and overlapping vegetation (such as it’s doing here). Although it’s most commonly yellow, as here, it can also show up in shades of brown or orangeish. It seems to be a widespread species, found across North America as well as in England, from what I can tell from Google results; it might even be holarctic. The common name of Insect-egg Slime Mould is easy to see the origin of, but the “Eggshell” and “Fragile” of the other two both refer to the fact that when the fruiting bodies are mature the outer shell of each little teardrop is quite brittle and will crack easily, releasing the black spores contained within.

Eggshell Slime Mould, Leocarpus fragilis


Not-exactly-dry rot


Sometime last summer, shortly after we’d moved in to the new house and settled our outdoor and garden things (and stuff that needed storing) into the shed, I noticed a fungus beginning to bloom from a crack in the floorboards. I kept meaning to take some photos and get an ID, but never did. This summer it returned, beginning from a slightly different spot in the boards than last year. I watched it grow with some interest, but it was only when it started to swallow the extension cord our lawnmower is plugged in to that I finally went and got my camera.

I sat down with my Lone Pine field guide to Mushrooms of Northeast North America, an excellent guide to fungi, well laid-out with good photos. Some 609 species are covered in the guide, and while this is only a sampling of the different species that occur in the region, the author does make a good effort to provide representation of all of the major groups, such that I can usually at least find a sister species that sets me on the right track, even if I might not find the actual species itself.

However, after several flip-throughs, I was drawing a blank. The only fungus that grew in sheets like this (a growth pattern for which species in the group are called “crust fungi”) that seemed to match was Phlebia radiata, but it wasn’t quite right, and images online didn’t match up. Other Google searches came up blank. Finally, a Facebook friend put me in touch with David Fischer of (he’s also a distinguished mycologist), who was able to put a name to my spreading fungus rather quickly.


It’s Serpula lacrymans, a species of fungus that contributes to dry rot. It is most often found affecting the interior of houses and other structures, and there are many photos online of the fungal growths. I did actually check out “dry rot” as a possibility while I was trying to come up with an ID, but the photos I looked at appeared completely different from the growth in our woodshed. It seems that substrate and location of the fruiting bodies will contribute to their shape and appearance.

The fungus will have a mycelium network (akin to the root system of trees) in the wooden floorboards of the shed; as with many fungi, fruiting bodies will only be put out from certain points of the mycelium. The fruiting bodies (I gather) can survive temperatures as low as 3°C (37°F), so will survive well into the fall here, but will die back from the winter. Indeed, this spring there was no sign of last year’s fungus, but a new one sprang up from the existing mycelium once the weather warmed up.

The fungus is a problem because the mycelium invades the wood and secretes and enzyme that begins to break it down. Though it does typically only invade damp wood, it doesn’t need much moisture in order to grow and survive – perhaps 30 to 40 percent moisture content in its host wood. The floorboards of the old woodshed undoubtedly have that; I don’t think they’re far separated from the ground, and while historically an interior wood stove might have kept the air inside dry, the building hasn’t seen such use in decades. The term “dry rot” doesn’t mean that no moisture is needed or involved, but rather that the fungus typically attacks the drier wood such as that used in construction, rather than the comparatively wet wood (with a relative moisture content of 100%) of newly- or recently-felled trees.


I have to admit that, despite knowing that the fungus is slowly eating away at the floorboards, I’m rather fascinated by it and tempted to let it be and watch it grow and change and take over the shed. Guess maybe I should let the landlord know…

The best of 2009

Black-capped Chickadees

Yesterday was my two-year “blogoversary”. (I actually thought today was, which is why I didn’t post yesterday; it was only in going back to review last year’s post that I realized my error.) I first put metaphorical pen to paper here at The Marvelous in Nature on January 12, 2008. It’s hard to believe two years have flown by already. Not including this one, I have written 449 posts here to date; 222 of those were since my one-year blogoversary post. That works out to about one every 1.6 days. This was probably boosted considerably by my habit of writing more frequently – sometimes up to five times a week – during the summer. I can’t sustain that sort of pace during the winter, when it’s more like one post every 2.3 days.

I thought in celebration of reaching the two-year mark I’d select my favourite posts from 2009 and re-share them here for those who might have missed them the first time, or would just like to enjoy them again. I did this last year, as well; for me, it’s fun to have a chance to review the past year and remember all of my interesting and exciting observations. Two-hundred twenty-two posts is a lot of writing; it was hard to select just twelve as my favourites, but I finally narrowed it down. So without further ado: the best of 2009!

Canadian picnic table

JanuaryI and the Bird #92 – The Picnic Party
I looked through all of my January posts from last year, and I had some interesting observations, but I finally settled on this one. I had a lot of fun when writing the poem, and I still have fun when I go back to read it. I’m hosting I and the Bird #117 next Thursday, nearly one year to the day from the picnic party edition.

Hoary Redpoll

FebruaryThe old man redpoll
We had a couple of Hoary Redpolls visit our feeders in February, and I discussed a bit about them, as well as identification tips to tell them from Commons.

Pileated Woodpecker

MarchA place to call home
While out wandering the woods with Raven I came across a female Pileated Woodpecker working on excavating her nest. She was very unconcerned with us, and kept working away even as I ran off dozens of photos from just below.

Wood Frogs

AprilWood frog love
While visiting some crown land north of the previous house I found a couple of female Wood Frogs being mauled by amorous suitors.

Canadian Columbine, Aquilegia canadensis

MayFlowers of the heart
Columbine are among my favourite wildflowers, and they were fairly common in the rocky habitat around the lake house. I hope we have some around here, too! We arrived too late last summer for them to still be in bloom. My sister got me one for my birthday last year, so I can enjoy them close to the house.


JuneIt’s a bug-eat-bug world
I collected up a number of photos of invertebrates I had encountered with prey (mostly spiders), and shared them together.

Spoon-leaved Sundew, Drosera spatulata

JulyThe plant that eats meat
Sundew are one of my favourite native plants, but are so rarely encountered because of their specialized habitat requirements that make them very local in distribution. I got a chance to check some out with the canoe on one visit to Rock Ridge this summer.


AugustL’otter fun
One morning, while I was sitting at the banding site at the Rock Ridge MAPS station, a family of otters swam by, through the water lilies and along the small lake below.


SeptemberBlack and blue and wet all over
When our landlord came to shut down the pool for the summer, he found a Blue-spotted Salamander in the filter intake, and brought it to share with me.

Netted Stinkhorn, Dictyophora duplicata

OctoberEau de la viande pourrie
My coolest mycological find of the year was this Netted Stinkhorn, one of a small handful I found over in the 100-acre woods.


NovemberWinterizing the brain
November’s a tough month for nature blogger – you’re suffering the post-summer letdown from the biological high you were riding for the last seven months, and in your slightly stupefied state of wildlife withdrawal it’s hard to come up with good content. As an exercise to help overcome the naturalist’s-block, I examine the small square of lichen-covered rock above.

Northern Cardinal

DecemberAll dressed in red
The cardinal that I first wrote about in this post still continues to grace us with his presence at the feeders. It’s good to see him doing so well!

Request for ID – Fungus or egg mass?

Brown woody mass on side of (poplar?) snag

I have great faith in the power of the nature blogging community to help others with identifications for mystery organisms and objects. Sometimes there are things you come across that you just can’t seem to find the right combination of search terms to produce a result and an ID on the web. You all came through on the comfrey I posted back in the summer. Now I’m asking for your help again; admittedly, this challenge is probably a little more difficult than the wildflower.

Brown woody mass on side of (poplar?) snag

I found this stuff in our cedar woods at the back of the property. The woods border on a bog/poor-fen, and are themselves rather wet. It’s nearly uniformly cedar, but there seem to be one or two tall poplars in the middle. Also mixed in are a few small snags that looked like they were maybe once upon a time also poplars, but were in any case not cedars. I found half a dozen of these small snags, and every single one of them had these brown cakey masses on the sides of the main trunk. I didn’t spot any small trees with this bark pattern that were still alive.

Brown woody mass on side of (poplar?) snag

They ranged in size from a few inches long to as much as seven or eight. Some were a rich brown, while others were nearly the same colour as the bark. All of them were covered, to some degree, with algae. And all of them had these tiny holes, about 2-3mm in diameter, clustered mostly around the edges and sparingly across the middle. I tried to peel it up to look underneath or assess its texture, but it was woody and firmly attached.

Brown woody mass on side of (poplar?) snag

My hypothesis was that these were egg masses of some sort of insect. I also considered fungal growths, but then what are the holes? I’m reminded of a post I did in the first couple of weeks of writing this blog, about the bracket fungus Cerrena unicolor, which has a symbiotic relationship with a horntail wasp, whose larvae feed on the fungus’ mycelium in exchange for carrying the fungus’ spores to its next host. The fungus then also uses pheromones to attract an ichneumon wasp that parasitizes the horntail larvae, presumably helping keep the horntails from going crazy and decimating the fungus’ root system. Maybe it is a fungus and there was something like that going on here?

Any thoughts?

Wet (in summer) cedar woods

Speaking of trees and stuff, the January edition of Festival of the Trees is up at Xenogere. Jason takes us on a walk through the Celebration Tree Grove in Dallas, Texas. I encourage you to head over and join him.

Sunday Snapshots – October on the Grand Trunk

Old maple tree

No, not the Canadian railway, nor the Asian road route, nor the Ankh-Morpork telegraph system (which I recently finished reading about). This particular grand trunk is growing in our front yard and belongs to a large, old maple tree. The trunk is covered in deeply ridged bark, which is in turn covered with colourful lichens, which in turn hosts many interesting critters.

I was out raking leaves yesterday, since the weather was quite mild; a relatively balmy 16 C (61 F). I set aside the rake before the sore spots on my thumbs got a chance to turn into blisters, but reluctant to go in just yet, I played ball with Raven for a little bit. In between tosses, while she was hunting for the ball in the long grass of the meadow, I examined the trunk of the tree. It initially caught my interest when I noticed some of the tiny little Bark Mycena that I had first observed on the maples of my parents’ old house, when my blog was still just a month-old fledgling.


I grabbed my camera and documented all the organisms I found on the trunk, between the ground and eye-level, yesterday afternoon. For the purposes of relating scale, all of these photos are taken at the same magnification and are the original out-of-the-camera image; I have not cropped any of them (although I did lighten a few since it was overcast and some of the photos were a little dark). Most people know how big an average pillbug (or maybe a sowbug; I forgot to check for tails) is – the size of the frame for the photos below is the same as for this one, to give you an idea of relative size. The only exceptions to this are the final three, which were too big to fit into the frame when fully zoomed-in.

Bark Mycena
Bark Mycena
Little moth
tiny unidentified moth
Winter firefly
Winter Firefly
jumping spider
jumping spider
snail shell
little snail shell
bagworm moth case
Bagworm moth case; probably the adult has died and it's full of eggs
Bark Mycena
Bark Mycena
black ant; probably Black Carpenter Ant
Little moth
tiny unidentified moth
Winter firefly
Winter Firefly
Bark Mycena
Bark Mycena
tiny spider
tiny unidentified spider
Saddled Leafhopper, not technically on the trunk, but very close. Note the greenish leafhopper in the upper left.
tussock moth caterpillar
Tussock moth caterpillar, very worn; maybe Banded or Yellow-based

The next three are at a different scale from the above, as they were too large to fit into the frame comfortably (or at all). They were also on the next tree over, so not strictly the same group, but I couldn’t resist including them as well.

Green Shield Bug
Green Stink Bug
Polyphemus Moth caterpillar
Polyphemus Moth caterpillar - similar to the Luna Moth cat but separated by the V-shaped mark on its rear end
Spiny Oak-Slug Moth caterpillar
Spiny Oak-Slug Moth caterpillar