Tom Volk's Fungus of the Month for September1998

This month's fungus is Boletus edulis, the King Bolete, Porcini, Steinpilz, or Cep

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Boletus edulis with me!One of the great pleasures of being a mycologist (of the sort I am anyway) is interacting with amateur mycologist and amateur mycology groups. I have been to the North American Mycological Association (NAMA) forays nine times in the past 10 years in many interesting parts of the country. In August 1997 the NAMA foray was in Colorado, and I complemented my trip there with the honor of being the invited mycologist at the annual foray of the New Mexico Mycological Society. I had a fantastic time, mostly because of the really nice people in the club, and partially because of the great assortment of mushrooms, most of which I had never seen before. A real treat for us to find and collect was this month's fungus of the month, Boletus edulis.

Boletus edulisThere are many common names for this mushroom; when a fungus has many common names it is either very good or very bad-- but at least well known. This one is a very good edible mushroom, sought after by mycophagists (mushroom eaters) all the world over. It dries very well and can be purchased in many local supermarkets now. But what excitement to find it in the forests!

Although it seems like it's very difficult to find at times, this can actually be a very abundant mushroom, and can be found as a mycorrhizal associate, usually with conifers. It appears to have an obligate association with the roots of these trees, aiding them in absorbing nutrients while receiving sugars from the tree's photosynthesis. In many places it is difficult to find them without magotts in them-- apparently these insect larvae prize this mushroom as much as we do. But the Boletus edulis in Colorado and New Mexico was almost completely free from worms. It was really fun to see people fill their baskets with pounds and pounds "of the best harvest in 25 years." They say some years there is none at all, depending on the rainfall.

Boletus edulis topSometimes this mushroom is difficult to find because it barely pokes its cap above the soil surface. Its elusiveness is compounded by the fact that sometimes it does not even push above the needles that have accumulated on the floor of the forest. Experienced mushroom hunters look for small "humps" in the litter that indicate these choice mushrooms are hiding underneath. But the mere presence of these "mushrumps" does not mean Boletus edulis is underneath. There are many kinds of mushrooms that do this. As with any mushroom, you must be absolutely sure what you're eating-- you must be able to identify a mushroom to species before even considering eating it. These pages are no substitute for taking a course in mushroom identification or learning a mushroom from a knowledgeable expert.

Boletus edulis reticulations on stemBoletus edulis is fairly easy to identify, once you get the hang of it and see all the variations in color and size and shape. One of the common features of all the varieties are the reticulation on the stem, easily seen in the picture on the right. If you don't know what reticulations are, think of the reticulated giraffe, the common giraffe we all have seen. The pattern on the giraffe is what is called reticulate. That's how I remember what reticulations are anyway...

There are probably a number of species in different parts of the world and different parts of this country that are masquerading under the name Boletus edulis. There's even some question of whether we have true Boletus edulis in North America, since the species was described from Europe. What we call Boletus edulis in Midwestern North America bears little resemblance even to what I saw in New Mexico, which is the closest I have seen to the European species, with its bulbous base and coloration.

Boletus barrowsiiOne example of this is a white variety that is found in New Mexico and Colorado and nearby places. It is now considered to be a different species and is called Boletus barrowsii, after Chuck Barrows, an amateur mycologist who found the species, and sent it to Alexander Smith at the University of Michigan, who named the fungus after Chuck. This is one of many examples of contributions by amateur mycologists to the field of mycology. There are many very good amateur mycologist, many of whom know their mushrooms better than I do! The line between professional and amateur mycologist can become very blurred!

Mount of the Holy Cross in ColoradoSo if you get a chance to get into the mountains of the southwestern United States you're in for a real treat. besides the abundance of mushrooms (if you're lucky and go at the right times) you also get to see beautiful scenery, such as the Mount of the Holy Cross in Colorado. (see the cross-shaped glacier on the mountain in the middle? You have to have a good imagination to be a mycologist...). There's many reasons to be associated with amateur mycology groups, and one of the best is the fun places you get to go. Contact the North American Mycological Association or see this list of check out Mykoweb's listing of North American Mushroom Clubs for one near you.

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This page and other pages are © Copyright 1998 by Thomas J. Volk, University of Wisconsin-La Crosse.

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