When: 2013-06-29

Collection location: Blewett Pass, Chelan and Kittatas Cos., Washington, USA [Click for map]


Who: Drew Henderson (Hendre17)

No specimen available

Very large Agaricus-fruiting under Douglas fir, Ponderosa pine and mixed deciduous canopy.

Note: cogwheel pattern on veil edge- near underside of cap margin-indicative for this species.


Base of stem very bulbous-almost like a large amanita without the girdle.

Gills: grey- darker purple near tips.

Found at 4000ft. near burn site.

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= Observer’s choice
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Me too
By: Christian (Christian Schwarz)
2013-07-01 16:12:51 EDT (-0400)

I am really looking forward to Kerrigan’s upcoming work.

The heat has taken hold down here as well…

Thanks Christian-
By: Drew Henderson (Hendre17)
2013-07-01 16:01:44 EDT (-0400)

Sorry for misunderstanding the placement suggestion for Sect. Arvense… I had read the literature from the early 1900’s from Peck- but also found a few pages in Margaret Mckenny’s book-“The New Savory Wild Mushroom” that implied A.abruptibulbous to be a bulbous form of A.silvicola. Thank you for your continued and extensive help and guidance on this site- greatly appreciated.

I agree that at this point we should place this observation in a section rather than a specific species… I am kicking myself for not bringing home a collection for microscopy and further study last weekend. Hopefully I’ll encounter it later this summer-altho- we are coming up on a week long stint of 100+ degree weather!

Thanks again for the info- and I too am looking forward to Rick’s upcoming book.

You’ve misunderstood
By: Christian (Christian Schwarz)
2013-07-01 15:17:57 EDT (-0400)

: Arvense is a Section of Agaricus, not a species.

First off, it’s worth noting that many, many species names are not very good descriptors of their actual characteristics… Agaricus lilaceps (lilac-headed) very very rarely shows that coloration. For that matter, Agaricus abruptibulbus as we understand it shows a large range in the degree of abruptness in the stipe base. So… names are not always useful to help with the identification process.

My point in proposing a less specific name was that we are sure that this is an Agaricus in section Arvense, but I, at least am not sure that A. abruptibulbus is a good name to use for it.

The flavescent alpine Agaricus of section Arvense in the west aren’t nomenclaturally resolved. Many people used to incorrectly call them A. albolutescens. Not only are there multiple species in the mountains, the conspecificity with the coastal entity that we’ve called A. abruptibulbus isn’t resolved.

Although I wasn’t able to find out the specific type locality, it looks to me like C.H. Peck described A. abruptibulbus from somewhere in the northeast… so there’s really not much precedent to suggest that our species would be the same as our western species(es).

Rick Kerrigan’s upcoming book may shed some light on the situation.

As far as I know

By: Drew Henderson (Hendre17)
2013-07-01 14:41:54 EDT (-0400)

Literally translates to “field” in latin… These were found at 4100ft. elevation deep in a Ponderosa and Douglas fir forest- not remotely near a meadow or grass.

The bulbous base, cogwheel pattern on margin, scent, yellow staining on stem and habitat all indicate A.abruptibulbus much more than A.arvensis, A.campestris, A.silvicola(which is sometimes synonymous with A.abruptibulbous) or any other all white, almond scented Agaricus.

Created: 2013-07-01 02:19:35 EDT (-0400)
Last modified: 2013-07-01 16:02:00 EDT (-0400)
Viewed: 128 times, last viewed: 2020-09-19 11:04:44 EDT (-0400)
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