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Observation 11189: Boletus L.

When: 2008-09-16

Collection location: Japan [Click for map]

Who: forestwander

No specimen available

I saw hundreds of these. There were probably thousands. The whole area smelled like them. The only way I can describe the smell is not appropriate for this site. So I will leave it to your experience or imagination.


Proposed Names

28% (1)
Recognized by sight: Pores instead of gills

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Three separate fungal things going on here:
By: Debbie Viess (amanitarita)
2008-09-20 20:03:10 PDT (-0700)

the tuber, whatever it turns out to be (try and cut one in half and take another photo; that would help!);

the bolete, which is much more colorful than the N. American parasiticus;

and finally, the “parasitic on a parasite” hypomyces, which starts white, then turns yellow (at least the species that we have here in N. America do; don’t know about your version).

your job is to try and beat the hypomyces at its own game and gather decent material before it is completely rotted! it may already be too late.

questions that I’d have…are ALL of the boletes that you see coming out of an underground fungus?
then the question is what is your "truffle/false truffle/secotioid whatever base, and then what is your bolete? if they are wildly common as you say, try searching some of the Japanese websites for a match. Whatever it is, and whoever knows what it is, I’d sure like to know, too!

good luck!

R. rubescens
By: Daniel B. Wheeler (Tuberale)
2008-09-20 14:56:24 PDT (-0700)

From Smith, Smith & Weber’s How to Know the Non-Gilled Mushrooms,p. 304: Fruiting body 1-6 cm, when young white and cottony-fibrillose, soon becoming sparsely covered with rhizomorphs at maturity appressed fibrillose and honey yellow to yellow ochre, exposed areas reddish brown, staining pink to vinaceous red where injured, with KOH vinaceous red to red-brown, with FeSO4 slowly greenish to olive; odor mile to disagreeable in age; gleba white and soft when young, dark olive brown and +/- gelatinous at maturity; spores 8-10 × 3.2-4 microns; peridium of hyaline to pale yellow hyphae over a vinaceous brown zone with considerable debris on and between the hyphae (as seen in KOH).
Solitary to cespitose (clustered) under conifers, especially 2-needle pines; summer and fall; often very abundant in lodgepole pine forests in late July and August, bu known across the continent. This is probably the commonest Rhizopogon in North America. Several varieties hve been described, based primarily on differences in the spores.

At least one specimen, found in Southern Oregon, reached well over 1 pound in size. My collections of is did not have an unpleasant odor, and I would gladly eat it if not parasitized. It is also known from Japan under pine trees, especially Monterey pine, which was imported and planted in plantations there. The Japanese are supposed to esteem it, and it is considered secondary only to matsutake (which is my favorite also).

White on Boletus
By: Daniel B. Wheeler (Tuberale)
2008-09-19 23:46:43 PDT (-0700)

Probably a fungus growing on the fungus which in turn is growing on yet another fungus. The white is the first stage, called Fusarium. It grows extremely rapidly, especially in warm, humid conditions. I have seen it envelope a freshly picked Bolete in 3 hours. It will later become something called Hypomyces chrysosporium. Photos of both stages should be on this website.

Yes, Dry.
By: Daniel B. Wheeler (Tuberale)
2008-09-19 23:43:35 PDT (-0700)

Slice specimens in 1/4-inch slabs, and dry where there is good air circulation around and over them. Mild heat speeds drying.

By: forestwander
2008-09-19 21:27:16 PDT (-0700)

Do I need to dry the specimens before mailing? If so, what is the best method? I have never mailed mushrooms before. Might as well ask you.

And on a lighter note:

I returned to the location today and saw one bolete growing to an enormous size. Frankly, I am so tired of seeing them that I didn’t take a photo. Now I wish I had. I will try to return tomorrow and get a photo of the huge one. I keep seeing huge red caps from a distance and they are all boletes that match the ones shown here.

MOST of the boletes didn’t make it to fully grown stage, however. They are wrapped in a white foam-like gauzy material, and look like they are rotting away. We are trying to get to the bottom of that.

This area is always both interesting and irritating. I find alot of mushrooms, even during dry spells, maybe because of the heavy forest cover but the smell of boletes is always too much, even before I noticed this white rot phenomenon.

With the last rains the Boletes have become something from a science fiction novel. They seem to be taking over the whole forest with their sweet-funk disgust. And the white rot is everywhere on them.

But Boletellus Emodensis (obs. 11197) is totally unaffected by the rot. All forms of Bolete are abundant right now. Thanks to your’all’s interest I will pay attention to which ones are rotting and which ones aren’t.

I added a few photos. But that is not the big fella I am talking about. Will try to get out there tomorrow to show you the big one.

Collect the base as well
By: Daniel B. Wheeler (Tuberale)
2008-09-19 14:06:57 PDT (-0700)

Should have been some unparasitized Rhizopogons nearby. I disagree with Debbie in this area. The base is probably a Rhizopogon, with a whitish basal coloration (but could be another color completely!). Note the trees nearby as well, since many Rhizopogons are associated only with a single species of tree.

The coloration to my eye is not white. Rather, the parasitic Boletus has produced red/dark pink rhizomorphs (mycelial threads, often compared to roots) which have engulfed the hypogeous fungus, and from which the mushroom has arisen. The parasitic Bolete has already degraded the interior (thanks for the photo!) to the extent it is unrecognizable, but it is most likely not the Elaphomyces granulatus we typically find in the Pacific Northwest which is parasitized by Boletus parasiticus. Thus what you have is a species new to me, and possibly new to the world. Please try to return to the area if possible, and collect the mushroom and the fungus the mushroom was likely growing on, cut both in 1/4-inch thick slices, take abundant photographs (including the nearby trees, if possible) and mail to Dr. James Trappe, c/o Forestry Sciences Lab, 3200 Jefferson Way, Corvallis, OR 97330. Identification is free, but please include a self-addressed, stamped postal card so Dr. Trappe can reply to you directly.

Boletus parasiticus is the only species I have in my books (Smith, Smith & Weber’s How to Know The Non-Gilled Mushrooms, c. 1981). There are, apparently, others. Japan is a well-described area for fungi, and I would be very surprised if this has not already been described somewhere in your area. It is similar, but not identifical to, Boletus parasiticus. Elaphomyces often has a thick peridium (outer shell) which is most frequently encased in a thick shell of rootlike rhizomorphs, none of which is apparent on your specimens.

all of the boletes were growing from this underground fungus?
By: Debbie Viess (amanitarita)
2008-09-19 08:16:13 PDT (-0700)

next time, cut one in half! the bad smell probably were due to the
mushrooms being rotted by Hypomyces (the whitish overgrowth on your boletes), altho some of the reddening rhizopogon(if indeed that is what your tuber turns out to be) also can have a foul smell. having you wander through YOUR local forest is highly educational to the rest of us on the other side of the world!

I have never heard of a rhizopogon fruiting boletes before, just Scleroderma.

Parasitic bolete.
By: Daniel B. Wheeler (Tuberale)
2008-09-19 01:11:46 PDT (-0700)

Only species I’m aware of are from the other side of the Pacific. Had they been growing on Elaphomyces, I might have had an idea. I’m going to guess that these were growing on Rhizopogon rubescens which had been well colonized by the parasiitc Bolet. R. rubescens is one of the larger subterranean Boletus look-alikes, and could fruit in the abundance necessary, if there were 2- or 5- needle pine trees nearby. Many Rhizopogon are species specific with a single host tree. Would need to know that info before making a better guess.

parasitic bolete? hypomyces? gastroboletus? take your pick!
By: Debbie Viess (amanitarita)
2008-09-16 14:13:05 PDT (-0700)

Seems like you have a couple of different fungi here…is that white lumpish thing hypomyces, a parasitic fungus, on another parasitic fungus?

and the top photo is way weird…looks like your little bolete is popping out of some sort of truffle or secotioid beastie…it’s colored like a gastroboletus.
did you cut it in half? and hundreds of these things?
too weird… but very cool.

By: Paul Derbyshire (Twizzler)
2008-09-16 03:08:25 PDT (-0700)

This might be one of the ones that’s parasitic on puffballs. I’m not sure from these photos, though.