Observation 181744: Leccinum Gray

When: 2014-10-05

Collection location: Splashdam Pond, Pennsylvania, USA [Click for map]

Who: Dave W (Dave W)

No specimen available

Collection made in same area as obs 181540 two days after 181540, during which time some rainfall occurred and the temperatures dropped a few degrees F below freezing.

Wet-looking area on upper part of sectioned mushroom very slowly developed a pink stain. This part of the mushroom had grown to a height above the surrounding grass/plants and had likely frozen for a couple hours.

KOH reddish-brown on cap and more prominently purple-brown on pores.

Proposed Names

58% (1)
Eye3 Eyes3
Recognized by sight
29% (1)
Recognized by sight: See comment.

Please login to propose your own names and vote on existing names.

Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
Thanks I.G.
By: Dave W (Dave W)
2014-10-08 07:12:46 NZDT (+1300)

No big surprise to me that the NA Leccinums are not considered to be well understood. I certainly have a difficult time trying to understand them!

The area where I have made many of my Leccinum collections (Splashdam Pond) is only 20-some miles from my home. Karen and I go there every fall to gather wild cranberries. But these Leccinum fruitings are becoming increasingly interesting to me. I’m hoping to get to this spot more often… maybe see what’s up next summer. I had previously supposed that two types of Leccinum occurred there, red-capped and gray/pale-capped types. But it’s becoming more apparent to me that the gray ones may represent 3 or more species.

The habitat consists of an old railroad bed/trail which skirts a wetland area, with wet areas common along/on the trail. Both sides of the trail are lined with a thicket of small/thin gray birch trees. The area gets lots of sunshine but never completely dries up.

I think one complicating matter (something of general interest to me) is that chemical reactions seem to vary with one or more of: weather conditions, the amount of time the mushroom(s) have been in existence, moisture content, habitat, time of year, or maybe something else I haven’t considered.

Last Sunday, when I made this collection, I had accidentally left my camera at home. I’m hoping to have time Thursday afternoon to get back out there and photo-document staining/chemical reactions as applied to small group fruitings.

These scaber stalks are very interesting… and pretty good edibles :-)

Leccinum taxonomy…
By: I. G. Safonov (IGSafonov)
2014-10-07 15:39:29 NZDT (+1300)

… in the USA is still pretty much in its infancy and much of it is still based the macro- and microscopic investigations of mycologists such as Smith & Thiers from 40-50 years ago. If you read Kuo’s discussion of Leccinum on MushroomExpert.com, it’s easy to see how much we are lagging behind the Europeans in terms of making progress toward sorting out and understanding North American scaber stalks.

To quote Roy Halling (from a recent personal communication):
I remember Harry Thiers telling me one time in the mid-80s that the survey of Leccinums by Smith, Thiers and Watling in northern Michigan was an exercise in describing populations (meaning, not species). He had no hard data to back that up, but just lots of time observing and describing them. Having heard that a preferred plant associate, aspen, is extremely abundant there, I’m not surprised that there is/was a ‘population explosion’.
I interpret what Harry said to be a statement of not knowing what the species boundaries of Leccinum really were. This was during the late 60s-early 70s when there just happened to be a tremendous flush of Leccinum, particularly in Montmorency County. That area had been clear cut and so the aspens and birches came back as pioneers. At least that’s how I understand it. So, they were describing every single thing they could document. At that time, rather than ‘lumping,’ they ‘split.’ I really think he was frustrated in not being able to get his mind around the amount of diversity (and biomass) present at the time

Personally, I find it frustrating enough to make any sense of whatever few Leccinum species we collect here in NJ. The real diversity comes from the mixed woods of birch, beech and hemlock found in the extreme north/northwest NJ, and I rarely go there. Apart from the easy ones, like L. albellum or L. rugociseps, the remainder (mostly consisting of orange- and brown-capped species) is still as elusive as it was when I embarked on my field identification studies of boletes some 8 years ago.

I am still trying to understand the morphology of a red-capped entity I find in the NJ Pinelands around this time of the year. I used to think that it was a single species. Now I am not so sure as the morphology, cap & scaber colors, and context staining are very variable. Perhaps there are two or three different species involved. On the other hand maybe I am just observing different populations of a single species…

Anyway, Dave, I really appreciate your attempt to sort out this collection and posting your ideas.

I sectioned two of these…
By: Dave W (Dave W)
2014-10-07 13:44:57 NZDT (+1300)

one with brownish scabers and another with black scabers. Left to sit out overnight, the one with brownish scabers slowly showed some pink staining that eventually turned to gray by morning. The one with blackish scabers slowly showed some spotty darkening and eventually developed greenish spot-stains in the lower stipe. The context of this one had become somewhat overall yellowish.

Looks like the possibility there’s (at least) two distinct species here.

Created: 2014-10-06 20:11:11 NZDT (+1300)
Last modified: 2014-10-07 13:39:43 NZDT (+1300)
Viewed: 52 times, last viewed: 2017-09-25 02:39:15 NZDT (+1300)
Show Log