Will I find the summer bolete in October?

The chances are slim. Of the 223 Ukrainian GBIF records for Boletus reticulatus, 70.3% fall in June and July and only 4.5% in October. This is a mushroom of late May, June and July, so in autumn an oak wood is more likely to give you the classic porcini.

What to pick in an oak wood in October?

Above all honey fungus on oak stumps and roots, wood blewit in the fallen leaves, brittlegills and the boletes from mixed patches. All of them need treatment, so have a look at how long to boil mushrooms.

Can you pick the bronze bolete?

Not in Ukraine. Bronze bolete (Boletus aereus) is listed in Ukraine's Red Book, third edition 2009, so there it has to be left alone; in most of Europe it is not protected. If an oak or beech wood hands you a dark, almost black bolete, photograph it and leave it growing.

How do you tell the oak-wood summer bolete from the bitter bolete?

By the underside of the cap and the net: in the bitter bolete the tube layer is pinkish and the net on the stem is dark, while in the porcini the underside is white or yellowish-green and the net is pale. A detailed comparison is on the page oak-wood summer bolete vs bitter bolete.

When does the lurid bolete grow, and how do you cook it?

The lurid bolete appears in June and holds on into September, so by October it is mostly gone. It is conditionally edible: boiling and pouring the water away is compulsory, at least 15 minutes of a real boil. More in lurid bolete: when it grows.

What soil does a productive oak wood have?

Acidic, well-drained, sandy. In a study of productive oak stands where the bolete fruited abundantly, soil acidity was pH 4.6. Heavy clay that holds water is far less promising. The whole picture by forest type is gathered in porcini in different forest types.

What mushrooms grow in an oak forest

Q: What mushrooms grow in an oak forest?

In summer it is the oak-wood summer bolete and lurid bolete, from autumn honey fungus on oak stumps, wood blewit in the fallen leaves and brittlegills. On mixed patches, add brown birch bolete and aspen bolete.

Q: Does the bitterness go away after boiling?

No, and that is not something to rely on. The milk cap descriptions state outright that the rufous milk cap (Lactarius rufus) stays acrid even after boiling. One bitter bolete can ruin the whole dish, so a bitter mushroom is better left out of the basket altogether.

An oak wood has its own mushroom calendar, and it is noticeably out of step with the one you know from pine woods.

Let's start with the honest part. If you are reading this in October and thinking about the oak-wood summer bolete, nobody goes looking for it now: it is a mushroom of late May, June and July. October oak woods have plenty to give, just something else entirely.

Below is the schedule as a table, then the detail on the summer bolete, on what autumn really offers, and on one dark bolete that is protected in Ukraine and should be left where it stands.

The table: what grows in an oak wood, and when

|---|---|---|---|

| **Summer bolete** (Boletus reticulatus) | late May–July | bright warm oak woods, forest edges, grassy clearings | a separate species, the net runs almost to the base of the stem |

One note on the table. Pure oak woods are rarer across Europe than they seem: oak almost always comes mixed with hornbeam, birch, aspen and lime. That is exactly why an “oak forest” happily gives you brown birch boletes and aspen boletes, even though neither is an oak mushroom.

The summer bolete means May, June and July

The oak-wood summer bolete (Boletus reticulatus, also known as B. aestivalis) is a recognised species in its own right, not a form of the classic porcini. And it has a season of its own, early summer.

The records show this unambiguously. Of the 223 Ukrainian GBIF records for Boletus reticulatus, 70.3% fall in June and July and only 4.5% in October. Which means nine chances in ten at this mushroom come before August.

So in autumn an oak wood can still give you the classic porcini, but for the summer bolete you come here on a different calendar. Where and under which trees to look for it in season we have set out separately: which trees the summer porcini grows under. And the whole picture by forest type is gathered in porcini in different forest types.

What an oak wood actually offers in October

October oak woods are not about boletes. A different trio does the work here.

**Honey fungus.** The main autumn mushroom of oak stumps and roots. It grows in clumps, so one lucky stump often fills the whole basket.

There is a serious warning here. The deadly poisonous funeral bell (Galerina marginata) grows on wood at exactly the same time, and the one difference you can rely on is the substrate: conifer wood means stop. If the stump or log is coniferous, you do not take mushrooms from it, however familiar the cap looks. Honey fungus is boiled for at least 30 minutes in any case, the water is poured away, and the first portion is kept small.

**Wood blewit.** The mushroom of the last warm weeks of autumn, from August into November. Look for it not with your eyes along the trunks but underfoot, in damp fallen leaves. Conditionally edible: boil 15 minutes and pour the water away.

**Bare-toothed russula** and the boletes from mixed patches, brown birch bolete and aspen bolete. They hold on until the real cold arrives, and they are the ones that most often save an autumn outing.

And the lurid bolete is mostly finished by October: its season is June–September. If you do come across one, treatment is compulsory — more in lurid bolete: when it grows.

Ukraine's Red Book: the dark bolete you leave standing

This is the most important paragraph on the page.

If an oak or beech wood hands you a dark, almost black bolete of a deep chestnut tone, it is most likely the bronze bolete (Boletus aereus). It is listed in Ukraine's Red Book (third edition, 2009). In Ukraine it must be left alone — in most of Europe it is not protected, and there you may legally pick it. Photograph it, admire it and leave it growing, so it can spread its spores.

In October such a meeting is unlikely: of the 23 Ukrainian GBIF records, 12 fall in July and only 5 in October. But the signs are worth knowing in advance, because you will be deciding in the forest, knife in hand.

What not to confuse: the bitter bolete

The classic mistake in an oak wood is not a poisonous mushroom but a bitter one. Bitter bolete resembles a porcini closely enough to end up in the basket, and is bitter enough to ruin the whole dish.

Look at two things:

The underside of the cap. In the bitter bolete the tube layer has a pinkish tint; in the porcini it is white or yellowish-green.
The net on the stem. In the bitter bolete it is dark and distinct; in the porcini it is pale.

If you need to, you can carefully touch a crumb of the flesh to the tip of your tongue: the bitter bolete is unbearably bitter, and you do not swallow the mushroom while doing it. But the pink pores and the dark net are the more reliable guide.

And separately, the thing not to count on: boiling does not cure bitterness. And this is not only about the bitter bolete. The milk cap descriptions put it plainly: the rufous milk cap (Lactarius rufus) stays acrid even after boiling. So a bitter mushroom does not “boil out”, it simply ruins the pan.

A point-by-point comparison of the features is on the pages oak-wood summer bolete vs bitter bolete and porcini vs bitter bolete.

Why two neighbouring oak woods behave differently

It happens: two similar oak stands a kilometre apart, and mushrooms in only one of them. Usually the oaks are not the point, the ground under them is.

Porcini leans towards acidic, well-drained, sandy soils. In a study of productive oak stands where the bolete fruited abundantly, soil acidity was pH 4.6, which is distinctly acidic ground.

What this means in practice:

Dry ground that lets water through quickly is more promising than heavy clay that holds puddles.
Bright warm patches, forest edges and grassy clearings give more than deep shady thicket.
If an oak wood has no boletes year after year, the soil may be exactly the reason, and walking it in circles is pointless.

Oak leaf litter, a thick layer of leaves, is another local quirk. A mushroom can be completely hidden in it, so in an oak wood it pays to look not for mushrooms but for little mounds and cracks in the leaves.

A basket from the oak wood, in the kitchen

An oak wood gives up a good number of conditionally edible mushrooms, so the kitchen part matters more here than in a pine wood.

The general rule for any wild mushroom: at least 15 minutes at a steady 70–80 °C right through the flesh. That same temperature, 70 °C, destroys echinococcus eggs that a mushroom can bring in from the forest. Keep a real steady boil, not a barely visible simmer.

Then by species:

Honey fungus. At least 30 minutes, pour the water away, keep the first portion small.
Wood blewit. 15 minutes, pour the water away, then fry, salt or freeze.
Lurid bolete. Boiling with the water poured away is compulsory; it is not eaten raw or undercooked.
Milk caps. Traditionally they go into salting. Boiling here is not about bitterness: a ten-minute boil in plenty of water (one part mushrooms to three parts water) with draining and rinsing in cold water is advised in a booklet on reducing caesium-137 content, not as a cure for bitterness.

The times for the rest of the species we have gathered in a separate cheat sheet, how long to boil mushrooms.

And on moderation. Ukraine's Public Health Centre advises no more than 200–250 g of wild mushrooms per adult per week, because mushrooms are hard to digest and take up whatever is in the soil. For children under 12 the same centre advises giving no wild mushrooms at all.

Finally, about what not to believe in the forest, even if you heard it from your parents. A silver spoon, an onion in the pot, “animals eat it, don't they”, bright colour and a pleasant taste are not tests for toxicity. And boiling does not destroy “any poison”. Only a mushroom you are sure of goes into the basket.

Sources

Boletus reticulatus in GBIF, Ukrainian records by month: 223 records, 70.3% in June and July.
Boletus aereus in GBIF, Ukrainian records by month: 23 records.
Red Book of Ukraine, third edition (2009), status of the bronze bolete.
Paper on the soils of productive oak stands in the journal Microorganisms (2025, vol. 13, no. 9, article 2196): acidity pH 4.6.
Guidance from the German Federal Institute for Risk Assessment (BfR) and the German Mycological Society (DGfM) on heat treatment of wild mushrooms, plus consumer guidance from the federal state of Hesse on heating to 70 °C.
Description of the rufous milk cap (Lactarius rufus) in a Swedish mushroom guide: the mushroom stays acrid even after boiling.
Booklet on reducing caesium-137 content in wild mushrooms: boiling milk caps and woolly milk caps for 10 minutes in water at 1:3 with draining.
Guidance from the Public Health Centre of Ukraine's Ministry of Health on eating wild mushrooms.