Monday, December 14, 2009

Decidedly amateurish mushroom ID

Last week, I brought home a big mushroom from the Watershed Park, and laid it out to take a spore print. I forgot to read the instructions in my field guide; it's been a long time.

What the book says:
"... cut off the mushroom's stalk close to the base. Place the cap, with the gills or pores facing down, on a piece of white paper. ... Sometimes the spores fall more readily if you place a drop of water on the cap before you cover it. Some mushrooms produce spore prints in a few hours; others take much longer, sometimes overnight."
What I did: the stalk was almost non-existent, and off to the side, so I didn't trim it. I put the cap, gills down, half-and half on a couple of pieces of paper, one white, one deep burgundy (because I didn't have black around at the moment). The two colours are to allow for white spores, which wouldn't show up on the white paper. I touched a wet fingertip to the top of the cap.

And I forgot to cover it.

I'll go back to the beginning. Half-way down the slope of the park, we passed this log:

For several metres down its length, these large grey mushrooms were sprouting. The large one on the left was a bit over four inches long.

They were grey, with a hint of brown, smooth and leathery. Colours are difficult to judge in the shade of these trees, but the drying ferns look about right, and this is the way I remember the mushrooms. I used the flash.

Testing their softness, I accidentally broke a large one off, so it came home with me. It was gilled, with an inrolled rim ...

Freshly harvested, on a log.

... and had a pleasant, "woodsy" scent. The stem, what there was of it, was whitish and wooly.

Microscope photo (40x) of the curly gills near the edge. They are straight for the rest of their length.

Compare to the mushroom on my table, a day later:

Now it is a rich brown, with hints of maroon. The lighting may have something to do with it, but again, I used the flash and corrected for white balance. This is the way it looked to my eyes.

And there is a blowout of spores on the dark paper, nothing visible on the white. But when I lifted the mushroom, there was nothing underneath. I replaced it carefully, and waited another day and a half. When nothing was happening, I gave up and examined the print.

On the burgundy, the sprayed dust looked bluish-gray. On the white, under a bright light, I could distinguish the merest hint of cream, also sprayed off to the side. Under the microscope, at 200x, all I could see was this same faint dust.

I changed the colour balance on this photo, and jacked up the saturation, to highlight the pattern. It seems that the mushroom casts its spores off to the side, instead of just dropping them. Could this be helpful in spreading the colony to the next log? Would it have dropped spores directly beneath the cap if I had remembered to cover it?

Questions, questions.

At least, having done all this, I should be able to identify the mushrooms, right? I think so. As far as I can tell, it is the Late fall oyster, Panellus serotina (-us), common in Europe and here in North America; I found a report from our Sunshine Coast. "Serotinus" means "late"; they fruit after the first frosts.

"The odd variation in cap colors is quite distinctive. This mushroom almost always fruits only after the first frosts of the season. Although considered edible, it is quite tough and must be cooked a long time over low heat." 
(Another, more technical description. "... sometimes bitter ... nausea ...") I don't think I'll plan on sampling the next ones I find.

My fumbling around notwithstanding, I'm pleased. I'll be taking more spore prints in the future. With a cover on top.


  1. I love to see the different types of mushrooms in the bush, but I'm a bit afraid of them. I don't know anything about identification and don't want to have any problems with the poisonous kind. - Margy

  2. Hi, Margy,
    It's fairly simple to avoid danger; just don't eat the mushrooms. Touching one won't hurt you.

    And I think the worst of our poisonous ones is the beautiful Amanita, which is easily recognized.


If your comment is on a post older than a week, it will be held for moderation. Sorry about that, but spammers seem to love old posts!

Also, I have word verification on, because I found out that not only do I get spam without it, but it gets passed on to anyone commenting in that thread. Not cool!