MycoNote

This English version was machine-translated from Ukrainian, so a few things may read a little off.

Birch webcap (Cortinarius triumphans)
Photo: Dragonòt · CC BY-SA 3.0 · source
Conditionally edible

Birch webcapCortinarius triumphans

Under review

Updated October 3, 2026

Passport

Edibility
Conditionally edible
Season
Aug — Oct
Hymenophore
Gilled
Cap color
Yellow
Size
Medium (5–15 cm)
Smell
Pleasant
Reviewed
Under review

Quick answers

Where to look?

Deciduous forest, Mixed forest

When does it appear?

Aug — Oct

Active months: August, September, October.

How to recognize it? Three signs

  • Cap color: Yellow, Orange, Brown
  • Cap shape: Convex, Flat
  • Smell: Pleasant

Fruiting season

Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

August – October

Description

The birch webcap, known to science as Cortinarius triumphans (in newer taxonomy often Phlegmacium triumphans), is a large, handsome mushroom with a slimy golden-ochre cap and distinctive brown bands on the stem. It belongs to the huge and treacherous webcap genus, named for the thin cobweb-like veil (cortina) that covers the gills in young mushrooms. It is a mycorrhizal mushroom that partners with birch, so you'll find it in birch and mixed forests.

In Ukraine, the birch webcap grows in birch groves, mixed forests and shelterbelts with birch throughout the country. It fruits in autumn — August through October; it appears in groups under birches among grass and moss.

The birch webcap is considered conditionally edible and calls for special caution. Although some guides call it edible, the webcap genus includes deadly poisonous species that accumulate orellanine — a toxin that causes irreversible kidney damage, with symptoms delayed by several days. Because the risk of confusing an edible webcap with a deadly one is so high, beginners are strongly advised not to collect mushrooms of this genus at all. So only take the birch webcap if you are absolutely certain of the identification, and at the slightest doubt, leave it be.

Cap

The cap of the birch webcap is large — 5 to 12 centimeters across. When young it is hemispherical with an inrolled margin; with age it opens to convex and flat. The surface is slimy and sticky in wet weather and glossy when dry. The color is golden-ochre, yellow-brown or honey-yellow, darker in the center and lighter at the edge, often with flattened fibers from the veil.

Hymenophore

The spore-bearing surface is made of gills. The gills are attached to the stem and fairly crowded, pale at first — cream or pale clay — and turning rusty-brown, brown from the spores as they mature. In young mushrooms they are covered by a cobweb-like veil (cortina), whose remnants settle on the stem as a brown band. The spore print is rusty-brown. Rusty gills and a cortina are the hallmarks of the webcap genus.

Stem

The stem is sturdy, cylindrical or club-shaped, 7 to 15 centimeters tall, whitish or pale yellow. Its defining feature is several yellowish-brown bands in the lower part, left over from the veil, and a rusty-brown band from the cortina near the top, where spore dust collects. There is no true ring. There is no volva.

Flesh

The flesh is whitish or pale yellow and firm, and barely changes color when cut. The taste is mild or slightly bitter. Because the mushroom belongs to the treacherous webcap genus, the flesh is no reliable guide: identifying it by taste or looks alone is dangerous, so at the slightest doubt, don't eat it.

Smell

The smell is faint, pleasant and mushroomy, with no sharp notes. Scent is not a reliable feature for safe identification. The mushroom is recognized by its slimy golden cap, rusty gills with a cortina, banded stem and association with birch — but even these features demand a great deal of experience.

›Scientific synonyms (2)

Phlegmacium triumphans (Fr.) Wünsche, Cortinarius crocolitus Quél. (1879)

Lookalikes

Mushrooms of the same genus and habitat — to study side by side and never mix up.

Frequently asked questions

Is Birch webcap edible or poisonous?
Birch webcap is conditionally edible. Before eating any wild mushroom, always double-check current information in reliable sources and consult an expert.
Does Birch webcap have gills or pores?
The spore-bearing surface (hymenophore) of Birch webcap: gilled.
What does the cap of Birch webcap look like?
The cap of the birch webcap is large — 5 to 12 centimeters across. When young it is hemispherical with an inrolled margin; with age it opens to convex and flat. The surface is slimy and sticky in wet weather and glossy when dry.
What does the stem of Birch webcap look like?
The stem is sturdy, cylindrical or club-shaped, 7 to 15 centimeters tall, whitish or pale yellow. Its defining feature is several yellowish-brown bands in the lower part, left over from the veil, and a rusty-brown band from the cortina…
What do Birch webcap smell and taste like?
The smell is faint, pleasant and mushroomy, with no sharp notes. Scent is not a reliable feature for safe identification. Taste: mild.
Where does Birch webcap grow?
Typical habitats: Deciduous forest, Mixed forest.
Which trees does Birch webcap grow under?
Birch webcap usually grows near: Birch.
When should you pick Birch webcap?
It fruits in: August, September, October.
What can Birch webcap be confused with?
Birch webcap can be mistaken for: Fool's webcap, Violet webcap, Red banded webcap, Gypsy mushroom, Cortinarius esculentus. Study the distinguishing features carefully — detailed comparisons are in the “Lookalikes” section.
How do you cook Birch webcap?
Birch webcap can be fried, boiled, pickled and dried. Before cooking, it's recommended to boil it for 10–15 minutes and drain the water.
Can you dry Birch webcap?
Yes, Birch webcap is well suited to drying and freezing. Dried mushrooms keep their aroma and work well in soups, sauces and fillings.
What is the scientific name of Birch webcap?
The Latin name is Cortinarius triumphans. It belongs to the genus Cortinarius, family Cortinariaceae.

Sources

  • [1]Вікіпедія (українська)
  • [2]Атлас грибів України, Зеров Д.К. (1979)
  • [3]MycoBank Database
  • [4]Index Fungorum
  • [5]GBIF
  • [6]iNaturalist Ukraine