Coprinus comatus, commonly known as the shaggy mane mushroom, shaggy ink cap, or the lawyer's wig, is generally considered to be a very easy mushroom to identify, but care must still be taken when identifying it.
In fact, it's generally considered to be one of the "foolproof five" which includes chicken mushrooms, black trumpets, morels, and giant puffballs.
I personally cannot emphasize enough, the "foolproof five" is a myth!
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| Shaggy mane starting to deliquesce, at this stage easy to ID, but less desirable as food |
Shaggy mane mushrooms can be, and frequently are mistaken for: Coprinopsis atramentaria (potentially poisonous), Chlorophyllum molybdites (very poisonous--but not deadly), and Amanita thiersii (possibly poisonous).
If you aren't trying to eat shaggy manes and can afford to wait thier whole life cycle, they are really easy to identify. The problem is, by the stage of thier life when they become easy to identify, they are no longer suitable to eat, because of deliquescence. As the mushroom ages, it deliquesces, eventually turning into a black goo.
The black goo is easy to identify, but not something you would want to eat.
As a forager, the trick is to find and identify the mushrooms before they start to deliquesce, and at that stage its possible to confuse the mushroom with a couple of others.
