Tom Volk's Fungus of the Month for November 1998

This month's fungus is Clitocybe nuda, the Wood Blewit.

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Also be sure to look at some seasonal Thanksgiving fungi -- check out my popular and newly revamped
Fungi that must be overcome to have a traditional Thanksgiving dinner.

Clitocybe nuda Here in the North it's starting to turn cold and when that happens we start to collect an unusually colored and delicious mushroom, Clitocybe nuda, also known as Lepista nuda. I'll have more to say about the name later. This mushroom likes very cold weather and sometimes fruits in great abundance, especially in duff or wood chips. Several years ago I found 15 pounds or so in the needle duff in a spruce plantation, and just last month I found about 20 pounds in wood mulch placed around ornamental arborvitae. It is a very strong flavored mushroom that dries and reconstitutes well, so I now have two gallon size bags filled with dried blewits for the winter.

Clitocybe nudaThe origin of the common name Blewit is pretty obvious-- buttons of the mushroom are very blue/purple. Most of the time, unfortunately, the color fades out to a dull brown as the fruiting bodies mature. You can usually see the remnants of the purple in the gills and sometimes in the flesh of the mushroom. It makes a beautiful addition to any dish. Some systematists place Clitocybe nuda into the genus Lepista, because of its tan to buff spore print. However in almost every other way it is a Clitocybe. We accept many shades of spore color in genera like Russula and Pleurotus, so I think we can accept a slight variation in spore color in Clitocybe-- so I prefer to follow Howard Bigelow, who wrote a monograph of the genus Clitocybe, and use the name Clitocybe nuda. You are free to use Lepista nuda if you like, but I am basically a "lumper."

Cortinarius atkinsonianusIf you're going to collect Clitocybe nuda for eating there are some precautions you will have to take. Novices are often surprised to learn there are a number of other purple mushrooms. Especially prevalent are purple Cortinarius species, such as the Cortinarius atkinsonianus shown on the left. Cortinarius species can be distinguished by their rusty brown spore print, mycorrhizal habit, and the presence of a cobwebby partial veil called a cortina, which is yellow in this species. There are at least eleven purple Cortinarius species, including C. violaceus, C. alboviolaceus and C. traganus. Cortinarius species should never be eaten, primarily because they have not been fully studied for toxins. More than sixty species of Cortinarius have been found to contain orellanine, a toxic cyclopeptide that causes serious damage to the kidneys, but only after a very long latent period; the first symptoms do not appear until 2-14 days after the mushroom has been eaten. About 15% of reported cases have been fatal. So you should be absolutely sure of what you are eating before you try Clitocybe nuda-- always make spore prints!!!

Clitocybe gibbaClitocybe clavipes

There are many other Clitocybe species that are common in my part of the world. To the left is Clitocybe gibba, and to the right is Clitocybe clavipes. I do not recommend eating either of these species. There is never any purple color on either of them, and they could be confused with Clitocybe dealbata, the "sweater," which causes severe cramps, sweating, crying and salivation. In addition Clitocybe clavipes contains an antabuse-like substance, so it should never be eaten in conjunction with alcohol. Please be careful when eating any wild fungi-- you must identify the specimens to species, and read a lot about similar species that may be poisonous in some way.

For a look at some seasonal Thanksgiving fungi check out my popular and newly revamped Fungi that must be overcome to have a traditional Thanksgiving dinner.

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