When a summer porcini is no longer worth picking

Finding a bolete is only half the job. The other half is honestly judging whether it's worth taking. The summer bolete (Boletus reticulatus, in our catalog the summer bolete) loses flavor with age, soaks up water and is almost always maggoty. A mushroom like that gets left in the forest, and not just out of squeamishness.

Being able to tell a young, firm bolete from an overripe one is the mark of an experienced forager. Let's look at what to check and why an old mushroom does more good where it stands than in your basket.

How to recognize an old mushroom

A few details give away a bolete's age, and the most reliable of them is the underside of the cap. Nature made the tube layer, or sponge, a handy ripeness indicator.

• white sponge a young mushroom, the best choice;
• yellowish sponge mature, still perfectly good;
• olive-green, soft, swollen sponge an old mushroom, one you no longer take.

Other signs of age: the cap has turned spongy and spread wide open, the stem has gone woody or, on the contrary, soft, and the mushroom itself is noticeably heavier than its size suggests because it has soaked up water. Press it with your finger: if the flesh springs back, the mushroom is young; if a dent stays, it's already overripe.

Maggots, the main reason to walk on by

Old boletes are almost always infested with larvae. The maggots often work their way up from below, through the stem, so the mushroom may look whole on the outside but be tunneled right through inside.

The check is simple: cut the mushroom lengthwise. A few tunnels in a young mushroom are no reason to throw it out; you just trim off the damaged part. But if the flesh is riddled with tunnels like a sponge, leave the mushroom in the forest. No dish will save it, and a mushroom like that won't do much for your appetite either.

Why an old mushroom is hard on the stomach

Even if an old bolete isn't maggoty, you shouldn't eat it. As a mushroom ages, protein breakdown products build up in it, and the flesh itself becomes limp and watery.

Mushrooms are fairly heavy food as it is, and overripe ones are even harder to digest and can cause digestive upset. The same rule applies as with doubtful mushrooms: if you're not sure it's fresh, don't take it. Your health matters more than one extra mushroom in the basket.

By the way, don't confuse an overripe bolete with the bitter bolete. An old bolete spoils because of age, while the bitter bolete is always bitter, even when young. These are different problems with the same result: an inedible dish.

Why leave old mushrooms in the forest

An overripe bolete is no use to us, but the forest really needs it. It's the old mushrooms that scatter the spores from which new mycelium grows.

A mature bolete releases millions of spores a day. By cutting or trampling every old mushroom, we rob the forest of its next harvest. That's why experienced foragers deliberately leave overripe specimens standing: it's an investment in next season.

A few simple habits of a caring forager:

1. take only young and mature mushrooms, leave old ones where they are;
2. don't kick over or trample what you're not taking;
3. cut or twist the mushroom out carefully, without tearing the mycelium;
4. don't dig up the litter looking for hidden mushrooms.

That way the spot will keep producing for years. And to come back exactly when the mushrooms are young and firm, keep an eye on the weather with our mushroom radar and head out in the first two or three days after a warm rain, while the boletes in deciduous forests are still fresh.

Sources

• “Identification Guide to the Fungi of Ukraine” (Kyiv, Naukova Dumka publishing house).
• Boletus reticulatus on GBIF, the global biodiversity database.
• Boletus reticulatus on MycoBank, the international fungal nomenclature database.
• Boletus reticulatus on Wikipedia.