Observation 11739: Lactarius Pers.

When: 2008-09-29

Collection location: Forest near Elgin St., Pembroke, Ontario, Canada [Click for map]

Who: Paul Derbyshire (Twizzler)

No specimen available

Little reddish mushrooms growing in the corner between the ground and a chunk of dead wood. Not sure if they were growing from the one or the other.

First six photos are of the larger mushroom on Sept. 29. Last two are of the smaller one on Oct. 4. Breaking the gills produced white latex.

In mixed woods.

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Proposed Names

92% (2)
Recognized by sight: gestalt fits, also can see small drops of latex in your gill close-up.

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Add Comment
great job relocating that mushroom. i’m impressed!
By: Debbie Viess (amanitarita)
2008-10-06 22:51:46 CST (+0800)
Good call!
By: Paul Derbyshire (Twizzler)
2008-10-06 14:59:12 CST (+0800)

I got back on Saturday, rather than Friday, and had a devil of a time locating the little bugger. I eventually spotted some other stuff I remembered seeing right around the same time, and checked carefully near the bases of pieces of wood in that area. Moving a fallen leaf exposed the remaining mushroom. It had gotten a bit larger. I photographed it in situ, turned it over, slashed a line across the gills, and bam! White latex. It was a milky all right. Eighth photo is of this mushroom overturned and “bleeding”.

Maybe on Friday
By: Paul Derbyshire (Twizzler)
2008-10-02 02:36:31 CST (+0800)

It’d take me an hour to get there, I have other plans, and it’s pouring rain.

Also, fuel may have gotten cheaper again recently, but it’s still not cheap in any absolute sense …

Bottom line — I can go there a couple times a week, but certainly not almost daily. :)

I’ll bet that stipe is brittle, too; try breaking it.
By: Debbie Viess (amanitarita)
2008-10-02 02:10:46 CST (+0800)

if it’s a lactarius (and not fulla bugs) it should break cleanly, like chalk.

By: Paul Derbyshire (Twizzler)
2008-10-02 02:07:03 CST (+0800)

I should have deliberately damaged this one. It might be a milky; I’m not sure if the white stuff in the gill close-up is latex or something else, like bug drool or something.

The smaller one was left undisturbed, and I may be able to do something with it on Friday or thereabouts.

The gills fork in a very interesting way; some of the short gills are forked from a point near the cap margin instead of at the inner end, but others are the usual way around. Gills and pores are not clearly separated, and forked gills, maze-gills, and elongated pores are intermediate states. Neither form of hymenium seems to form a monophyletic group. Even having some sort of gills-or-pores has apparently evolved multiple times, independently. Some ascos even have “pores” — the morels, with shallow and large outward-and-upward-facing ones (the preferred orientation for ascos due to how asci propel spores). Perithecia in Cordyceps and Xylaria might also be thought of as an asco form of pores.

Spines also evolved repeatedly. The surface area can be as high as with pores, but spines expose the developing spores more to the environment, which is probably why they are less frequent. Coral fungi can even be considered to have gone the spine route, dropping spores from cylinder surfaces that surround flesh rather than space as they do.

The curious rarity though is concentric gills. One polypore is known to employ this geometry, but it seems particularly useful — simplicity, high shielding of the developing spores from the environment, and material efficiency. (Pores are more volume-efficient than gills, but use more material per unit volume to construct.) Concentric gills, in particular, can remain at a fixed separation without the complexity of having short gills or forked ones.

(The wavier and more irregular mushroom caps seem to have used another surface area booster: hyperbolic geometry!)