What are Boletes?

Mushroom hunters refer to fungi in the genus Boletus as boletes. Because boletes all belong to the same genus, they share many characteristics. However, the individual species also vary quite widely: some boletes are tasty edibles, while others will cause severe gastrointestinal distress. Boletes are harvested all over the world, although they are not a good choice for inexperienced mushroom hunters, as proper identification can be tricky.

All boletes have meaty flesh, and a large cap with a sponge like underside. The spongy look comes from the way in which boletes produce spores, in a series of hollow tubes which are packed tightly together, creating the look of a fleshy sponge. Boletes are quite fragile, usually emerging the day after a rain, and becoming soggy and insect infested shortly thereafter. For this reason, the window in which boletes can be harvested is very small. Edible boletes should be cooked or dried the day they are found.

Boletes form symbiotic relationships with conifer trees such as the spruce. They can be found popping up in moist conifer forests all over the world, and will appear year after year in the same location because of the relationship they have with their host trees. If a mushroom hunter finds a dependable patch of the mushrooms, it is usually highly prized.

The most popular edible bolete is Boletus edulis, known in the United States as the King Bolete, in Italy as the Porcini, and as Steinpilz in Germany. The King Bolete can get very large, up to one foot (30 centimeters) across, with a thick fleshy stem. The mushroom has a brown top and a creamy white underside with brownish spores. The King Bolete has a slightly nutty flavor, which pairs well with the extremely fleshy texture of the mushroom.

Boletes which can cause intestinal distress often resemble the King Bolete superficially, although they tend to be smaller. If uncertain about the identification of a bolete, nicking the cap to see if it bruises can be a good way to eliminate certain toxic boletes, although this must be done when the mushroom is fresh. This isn't the most reliable way, though, since toxic and some non-toxic boletes will bruise a bright blue. A spore print can also be used to identify these mushrooms: cut the stem from the mushroom and place it on a piece of white paper, cap up. Remove the mushroom after one hour, which will reveal an attractive spore print that can assist in mushroom identification.

Edible boletes are sometimes available for commercial sale, and are often available dried as well. For inexperienced mushroom hunters, the mushroom should be collected in the company of individuals who are knowledgeable about boletes, or harvested in the wilds of the grocery store for safety. Use of a mushroom guide which includes an extensive key can also assist people who would like to learn about this incredibly varied genus.