The Cortinarius genus is one of my favorites. It yields a number of big and beautiful mushrooms with colorful features. These attractive gilled mushrooms are a family of fungi with orangish to tan to cinnamon brown colored spore prints, issued from gills on this mycorrhizal fungi which grow from a universal veil. This family features some very familiar mushrooms that also are some of the most toxic. Like Amanitas, a couple of cortinarius fungi are deadly, most are at least mildly poisonous. Only a couple are decent edibles, but my personal recommendation is to avoid collecting them to eat unless with an extremely knowledgeable or experienced forager. Please do, however, collect a few specimens of whatever you find for building knowledge, confidence and skill in the hunt for a positive identification (even if you never plan on eating a cortinarius).
What to look for in Cortinarius
As noted above, all “corts” grow from soil and have gills. Often the gills are a beautiful shade of purple or sometimes blue or pink. The gills of the cortinarius genus are not what I would describe as widely spaced, nor super crowded. Young specimens have gills hidden behind the cortina, which is a cottony veil over the mushroom. As the mushroom’s cap opens up and the mushroom matures, the veil collapses and sometimes leaves a cottony residue on the stem--though not typically a “ring” as you
might see on an amanita.
If the cortinarius is colorful, it is usually the cortina or the gills which have a showy color, but as the mushroom matures, these colors fade to a more subdued and often earthy color of beige, tan, or brown. There are also many cortinarius mushrooms which are not at all colorful and are just another LBM.
All corts have a rusty orange to cinnamon brown spore print or somewhere in between. Often an older specimen’s gills will have turned some shade of brown, revealing its spore color. Sometimes the veil left on the stem will also leave a spore print, turning the stem to the same shade of brown the gills have taken on.
Identifying corts to the exact species can be exceedingly difficult. It’s worth noting that there are also very few edible species of cortinarius--one of the few being the Gypsy mushroom. There are many poisonous corts and a few considered to be deadly. Personally, I stop to note and admire but I never eat these. The Gypsy mushroom, which is the only one worth eating, to my understanding, is not super common in the midwest and so I have not set myself on knowing it well.
With that said, I do enjoy eating Blewitts, which definitely have a few lookalikes in the cortinarius genus. To disambiguate, you MUST do a spore print. A Blewitt will have a creamy or lilac spore print. A cort will never have such a pale spore print and will most likely be some shade of reddish brown.