Tuesday 14 May 2019

Half-free morels and Verpa - The Fake False Real False Morels

Left: Morchella populiphila
Right: Verpa bohemica


Today's topic seems to be a bit of a stumper for many, who don't spend a lot of time working with, or identifying a variety of mushrooms: This LOOKS a bit like a Morel, but the cap doesn't meed the stem at the bottom. Is it poisonous?

The answer is, most probably, "No."

You probably have one of 5 species of fungi, on which there seems to be a lot of confusion. So let's work to clear the air.

North America hosts two species of "Half-free Morels", Morchella punctipes, and Morchella populiphila. These are morphologically similar, but easy to tell from the most common Verpa species, Verpa bohemica and Verpa conica.

While they are in the same family, Morchellaceae, they are different genera (Morchella and Verpa, respectively), and have differing characteristics by which they can be recognized.

Both are considered, by many, to be "true" Morels, and both are equally edible. The distinction between Verpa and "Morels" seems to be mostly a North American thing.

Morchella: West side vs. East side

The first difference that I want to address is specific to the Morchella species. 

There are two species of "Half-Free Morel" in North America - Morchella punctipes, and Morchella populiphila.. (Morchella semilibera is not a North American species).

Morphologically, they are pretty much identical, but they differ in location and host tree. In the west side of the country are M. popuphila, which live with Populus spp. (Cottonwoods).

The east has M. punctipes under various hardwoods. 


Verpa: Two species (OK, there are more, but we're focusing here!)

There are two species of Verpa of concern -  Verpa bohemica and Verpa conica. There are other species in this genus, but these are the most commonly found, and the most commonly confused with the aforementioned Morchella. 

V. conica is easy to differentiate from V. bohemica and Morchella, because the "cap" is smooth, without sharp wrinkles.

V. bohemica is the one that is most commonly mistaken for Morchella.



Here are the key morphological differences between the two genera:

Cap: 

  • Morchella - The cap is made of ridged, or netted tissue. It has sharply defined ridges or netting and pits.
  • Verpa bohemica - the cap is comprised of sharply folded tissue. A cross-section will reveal the difference, if you're uncertain by looking at it.
  • Verpa conica: The cap is smooth, without much texture or folded tissue. 

Stipe:

  • Morchella: The stipe is granulose (grainy, with many tiny bumps) in most specimens and generally completely hollow through the attachment to the cap.
  • Verpa: The stipe is smoother and, often, filled with a cottony pith. In older specimens gaps can develop in the pith, giving a hollow impression, but the walls of the cavity are generally quite moist in this case. The stipe may also show some lateral striations, though it does not have the granulose appearance of Morchella. 

Cap attachment:

  • Morchella: The stipe meets up and attaches to the cap part-way down the length of the cap (thus the "half-free" designation). In many cases, especially younger speciment, the attachment point appears constricted within the stipe, giving the appearance of a triangular cavity at the top. 
  • Verpa: In both Verpa species, the stipe only connects to the cap at the apex of the cap, leaving the cap sitting, like a thimble, atop the stipe. 

Aroma

  • Morchella: Well... they smell like Morels. A similar aroma to the Morel aromas with which you are already (presumably) familiar. 
  • Verpa: The aroma of Verpa is distinctive, and with some experience, a person can tell between the two, using this characteristic, alone. Verpa have an aroma that is reminiscent of chlorine or semen, sometimes also described as slightly metallic. This aroma fades, however, when cooked. 

Edibility: 


Both genera are edible, and excellent. Contrary to mythology, both the stipe and the cap of the mushroom are fully edible, and (in my opinion) the Verpa stipe is even more flavorful than the cap. 

Yes, some people have adverse reactions to Verpa... or Morchella. Adverse reactions include gastric distress and nausea. These are more inline with the symptoms of a food intolerance, and can be caused by any species of mushroom (or any other food). 

However, NAMA toxicology records indicate that both should probably be treated as toxic when raw or undercooked. 

There have been a number of reports of neurological symptoms such as loss of coordination, sneezing, numbness, dizziness, and others which have been linked to Morchella spp. (ALL Morchella species - not just the two described in this article), and to a lesser extent, Verpa spp. 

Therefore, be certain to always cook Morchella or Verpa thoroughly before ingesting. 

All of these mushrooms are very enjoyable to find, and eat. This article should help you to differentiate between them. 

Happy hunting! 

Verpa bohemica


Verpa Bohemica - bisected


Verpa bohemica - In some cases, the cap can dry up a bit, and closely resemble the ridges of Morchella, but the stipe is clearly Verpa.


Left:Young specimens of Morchella populiphila, bisected and whole.
Right: Verpa bohemica, bisected and whole

Morchella punctipes
(NOTE: This image came from Midwest American Mycological Information's Web page.) 

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