Observation 171661: Boletus pseudosulphureus Kallenb.
When: 2014-07-28
Who: jfwayne
No herbarium specimen

Notes: It looks a lot like S. tomentosus however I found this in the south east. It was on pine straw so it may be imported but other than that it matches up to much mushroom finders guide. Before I consume it I would love to verify this is S. tomentosus and edible. Thank you guys!


image (1).jpeg
image (5).jpeg
image (3).jpeg
image (8).jpeg
image (9).jpeg
Here’s a photo of the base of the big one
Turning blue/green slowly getting darker not immediately changing color
Turning blue/green slowly getting darker not immediately changing color

Proposed Names

-70% (3)
Recognized by sight
Used references
21% (3)
Recognized by sight
11% (3)
Used references: Arora, Mushrooms Demystified. Base of stipe reticulate. Stains when cut. Pores also have greenish-brown staining, possibly from handling.
-18% (2)
Used references: Kuo’s Bolete Key at MushroomExpert.com One test for determining B. subgraveolens is using ammonia on the blue-portion of the stipe or cap. If it changes back to normal coloration, it may be B. subgraveolens, according to Kuo.
14% (4)
Recognized by sight
32% (3)
Recognized by sight: Or the American similar species. Bessettes & Roody state sometimes reticulate.

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

Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
I am corrected.
By: Daniel B. Wheeler (Tuberale)
2014-07-31 14:38:40 PDT (-0700)

Thanks Ron, Christian, and Richard for pointing out an interesting exception. I had hardly knew of Buchwaldoboletus before.

Buchwaldoboletus is a small group of saprophytic and lignicolous boletes
By: Ron Pastorino (Ronpast)
2014-07-31 14:12:33 PDT (-0700)

that include the former Boletus hemichrysus and Boletus sphaerocephllus. They apparently have not yet been thoroughly studied and have had very limited DNA work done on them. This paper can be googled for further details…

Bulletin of the Buffalo Society of Natural Sciences, Volume 40, 2011 1

Beatriz Ortiz-Santana
Center for Forest Mycology Research, US-Forest Service Northern Research Station
One Gifford Pinchot Drive, Madison, Wisconsin 53726
Ernst E. Both
Buffalo Museum of Science, 1020 Humboldt Parkway, Buffalo, New York 14211
ABSTRACT – Buchwaldoboletus is a small genus of about a dozen species with a world-wide
distribution. The boletes of this genus are non-mycorrhizal, saprophytic and lignicolous.

I think Martin’s MO #144581 is Buchwaldoboletus hemichrysus due to the “yellow dust” on the cap.

This one could be Buchwaldoboletus sphaerocephalus, with a yellowish glabrous cap, and growing in caespitose clusters…perhaps on pine dust/residue.

By: Christian (Christian Schwarz)
2014-07-31 13:50:24 PDT (-0700)

They are super bizarre – the sclerotia of the Boletinellus house aphids that feed only on ash, and which secrete carbohydrates. The mycelium absorbs those sugars. So it’s kind of like an arthropod-mediated proxy-mycorrhizal association. Really, really cool.

By: Richard and Danielle Kneal (bloodworm)
2014-07-31 12:33:11 PDT (-0700)

what about Boletinellus merulioides?
if Ash is not considered to be ectomycorrhizal…
why is this fungus always associated with that tree type?

Not quite, Daniel
By: Christian (Christian Schwarz)
2014-07-31 11:51:54 PDT (-0700)

There are definitely saprobic boletes.
Some of the Buchwaldoboletus for example:
observation 27068
Not to mention the saprobic Phlebopus… and then there’s the uncertain but probably saprobic Boletellus ananas and its relatives, and then you have Boletus parasiticus, which isn’t sapropbic, but is definitely not mycorrhizal, and then there’s the weird mutualist/saprobic but not mycorrhizal Boletinellus merulioides.

Yes and no, Dave.
By: Daniel B. Wheeler (Tuberale)
2014-07-31 10:51:41 PDT (-0700)

No known bolete grows saprobically. I.e., no known bolete grows by consuming dead pine straw. Boletes mirabilis grows from rotting wood, but is still mycorrhizal.

And yes, “all physical science is the result of observation”. But earlier observations didn’t consider fungi forming mycorrhizae with host plants. Even today many do not consider that when identifying a species novum fungi.

You are correct that it should apply, but often is not included. Until certain fungi were shown to be mycorrhizal in the 1970’s, association with specific tree species was mostly ignored. Once the Tubers were found to (in many cases) be species specific, or found only with a specific species of tree was that added to observations. (I kind of wonder about whether Amanitas may be, in some cases, species specific as well.)

You can’t note something in an observation if you don’t know it is relevant. Thus the original observation of Tuber gibbosum was “found in mixed woods”. Which is really little more than saying it was found somewhere in a wooded area. The relatively wide area mycorrhizal fungi can develop underground with trees makes the observation further confused. But once you say “found in Douglas-fir Christmas tree plantation”, you have reduced other possibilities.

Even today there are few such reliable references we can make with mycorrhizal fungi, nearly 30 years after the NATS database made such observation important to every collection submitted.

For jfwayne, from all of us on MO: you’re welcome. It’s nice to know someone else reads us.

First time poster
By: jfwayne
2014-07-30 19:59:17 PDT (-0700)

Guys, this is my first time posting here and while I have enjoyed the local chanterelles and herecium, this has been an awesome experience and thank you for all your help I have really learned a lot. I’m still confused as hell but I’m really glad I came about this forum you all have been truly amazing!

So this may be one of the exceptions.
By: Dave W (Dave W)
2014-07-30 18:30:41 PDT (-0700)

That is, a saprobic bolete. They may actually be growing from pine straw/needles…!?

The NA bolete book doesn’t even include genus Buchwaldoboletus. Is this a relatively newly named genus? There are a few MO obses.

Good point about the lack of a pulverulent (powdered) cap surface, Martin. I wonder if this trait may be lost due to rainfall.

Daniel, all physical science is the result of observation. There is no “proof” in physical science, only verification (or lack of verification) of existing theory via new observations. But logic still applies. For example, if observations indicate that mushroom X has not ever been recorded as occurring in a location where tree Y grows, then one reasons upon the evidence to conclude that tree Y is not a mycorrhizal associate of mushroom X.

By: Martin Livezey (MLivezey)
2014-07-30 17:56:52 PDT (-0700)

no good closeup of the cap. Here is the only Buchwaldoboletus I have come across. The cap was powdery yellow – so powdery that it would mark your hand yellow. It was under pine. I read a comment on MO about a western Buchwaldoboletus that indicated the genus is saprobic, not mycorrhizal.


It may be a matter of observation, Dave W.
By: Daniel B. Wheeler (Tuberale)
2014-07-30 10:36:13 PDT (-0700)

You are correct that most boletes are mycorrhizal.

Professional mycologists often do not note potential mycorrhizal host trees. Many mycologists have a problem identifying the probable host trees.

So while North American Boletes says “oak with Loblolly pine nearby”, we still don’t know what species of oak is present, or whether it is the probable host. In fact we still don’t know which is the likely mycorrhizal host. It could be either. There was pine needle duff near where this obs. was fruiting. Almost anywhere there is pine duff, there are pine trees within the mycorrhizal range. I would suggest Loblolly pine as possible mycorrhizal host, instead of oak. If anyone has grown this fungus I will of course defer to their skills. To date I have not heard of anyone attempting to grow Boletus subgraveolens. Maybe that’s why it’s so rarely reported? As for the reticulations on the stipe, same thing applies. This could be a variant, subspecies, or different species.

Mycologists have much to learn from mycorrhizal relationships. Cultivation is one aspect. Recognition of soil types is another. Age of host trees is yet another, since it is known that many of the fungi on the ROD for the Northern Spotted Owl are associated with old-growth trees.

It was growing underneath a living tree
By: jfwayne
2014-07-30 09:47:09 PDT (-0700)

The tree was a new transplant so this is still likely

So this one may be a hardwood associate.
By: Dave W (Dave W)
2014-07-30 07:49:48 PDT (-0700)

This lends confidence to the subgraveolens proposal. However, the reticulate stipe is still a problem to fit in with this species.

With some exceptions, most boletes grow as a result of a fungal association with a living tree. Although it may have appeared that these boletes were growing on the pine straw (needles?), it is unlikely this is the actual host for the mushrooms seen in this obs.

Broad leaf tree
By: jfwayne
2014-07-30 07:38:30 PDT (-0700)

It was under a broad leaf tree but growing on the pine straw. They were planted trees I’m not sure what type

In the book North American Boletes…
By: Dave W (Dave W)
2014-07-30 05:52:17 PDT (-0700)

the description of B. subgraveolens does not mention reticulations on the stipe. The description does prominently mention a pruinose reddish stipe base. Also, the habitat is listed as “on the ground under broadleaf trees.”

Looks to me like B. subgraveolens is not a good match for this obs.

No information about this mushroom
By: jfwayne
2014-07-30 05:03:01 PDT (-0700)

I cannot find anything about this mushroom online how weird!

By: jfwayne
2014-07-30 04:55:33 PDT (-0700)

yep, those trees are found near me see a few in my back yard and there are those by the trail as well. So are we certain it is Boletus Subgraveolens?

Based on debris in photos 3 and 6,
By: Daniel B. Wheeler (Tuberale)
2014-07-29 21:52:01 PDT (-0700)

host tree is Pinus taeda, or Loblolly pine. Needles in groups of 3. Very fast growing in Georgia, but found throughout the south. Does that sound right, jfwayne?

New pictures
By: jfwayne
2014-07-29 20:41:00 PDT (-0700)

Added pictures from the pine straw not sure if local but Georgia pines are around all over but this was by newly planted trees I think it was from that pine straw and not from local trees. Also I just cut it now and it’s a bit old slow bluing no line down the middle

Other than Boletus
By: Daniel B. Wheeler (Tuberale)
2014-07-29 17:29:46 PDT (-0700)

I’m not prepared to offer a species epithet. As Walt mentioned, not Boletus pseudosulphureus, which I was looking at closely. You may have something in GA that is new or undescribed at this time.

If you go collecting in the area again, could you show photos of the entire fungus, including the base? Also include at least one photo of a sectioned mushroom through the stipe and cap?

Regarding edibility, I’ve always heard to stay away from blue- or red-staining boletes. Usually that refers to red pores, but I’d be very cautious trying an species we’re not sure of.

One other thing that might help: any idea of what species of pine was nearby, say within 200 feet of where the fungus was found?

Not Gyroporus
By: walt sturgeon (Mycowalt)
2014-07-29 15:43:05 PDT (-0700)

Boletus pseudosulphureus is a possibility but the reticulations don’t fit the original description.

Gyroporus cyanescens
By: jfwayne
2014-07-29 15:38:08 PDT (-0700)

could this be a possible answer as well? I don’t think it turned blue as quickly as this mushroom says it’s supposed to

Upon cutting
By: jfwayne
2014-07-29 15:06:01 PDT (-0700)

When it was cut they turned slowly from a green to blue to pretty dark possibly brown. Only one turned a red orange which was quite odd. It may match yellow cracked bolete with similar looking stem

Any ideas about specifics?
By: jfwayne
2014-07-29 15:03:29 PDT (-0700)

Yellow cracked bolete?

Fourth photo shows reticulation
By: Daniel B. Wheeler (Tuberale)
2014-07-29 15:02:23 PDT (-0700)

(netting) on stipe near cut. Stipe seems to be reddish there as well.

When cut, what color would you say this is, jfwayne?

Definitely not a Suillus
By: Christian (Christian Schwarz)
2014-07-29 13:42:57 PDT (-0700)

the reticulate stipe and dry cap, without a veil zone or glandular dots rule that genus out.

Created: 2014-07-29 13:15:18 PDT (-0700)
Last modified: 2014-07-31 18:08:50 PDT (-0700)
Viewed: 212 times, last viewed: 2016-10-21 18:29:25 PDT (-0700)
Show Log