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Aspen

Aspen — mushrooms with the trait «Aspen»

Aspen groves are often associated with damp lowlands and dense undergrowth. Although the aspen (Populus tremula) doesn't have as many mycorrhizal partners as the oak or pine, it is mother to one of the most beautiful and sought-after mushrooms of European forests.

24 species in the database.

The mycorrhizal bond and the famous red-capped boletes

The aspen belongs to the willow family and has a branching, shallow root system that is ideal for forming ectomycorrhiza. In her "Key to the Fungi of Ukraine," M. Ya. Zerova singles out this tree's main and undisputed companion — the red-capped scaber stalk.

In his guide "Mushrooms," Roger Phillips describes the red-capped scaber stalk (Leccinum aurantiacum) as a perfect example of species-specific mycorrhizal attachment. This splendid pored mushroom with a bright orange or red cap and a firm stem covered in dark scales grows almost exclusively under aspens. Its cut flesh quickly darkens, turning purplish-black.

Besides the red-capped scaber stalk, in "Mushrooms Demystified" David Arora mentions other mushrooms that form mycorrhiza with the aspen:

- Aspen milk cap (Lactarius tremulae): A small whitish mushroom that exudes an acrid milk. It's rarely used, mostly for salting.

- Brittlegills (Russula): Some brittlegill species, especially those with red and pink caps, are common in aspen forests.

- Webcaps (Cortinarius): A large group of mushrooms, many of them poisonous, so they call for caution.

Wood-decaying fungi on aspen

Aspen wood is soft and very quickly falls prey to saprotrophic fungi (if the tree is dead) or parasites (if it's alive). On old and fallen aspens you can often find:

- Oyster mushroom (Pleurotus ostreatus): In the autumn months, aspen logs are often completely covered with "shelves" of oyster mushrooms.

- Bracket fungi: Various bracket fungi, including the false aspen tinder fungus (Phellinus tremulae), which causes heart rot in living trees.

Questions and answers

Why can you sometimes find a red-capped bolete away from aspens?
The genus Leccinum (red-capped and birch boletes) is very diverse. True Leccinum aurantiacum grows only with aspen. But it has look-alike sister species: for example, the foxy bolete (Leccinum vulpinum) grows under pines, and the orange oak bolete (Leccinum quercinum) under oaks. Visually they are almost identical.
Are there porcini under aspens?
In pure aspen groves with no other trees mixed in (oak, birch, pine), you're practically never going to find porcini (Boletus edulis), because it doesn't form mycorrhiza with the aspen.
Can you eat the aspen bracket fungus?
No. The bracket fungi that grow on aspen trunks (including Phellinus tremulae) are extremely tough (woody) and have no culinary value whatsoever.
Do poisonous amanitas grow under aspens?
Yes. The fly agaric (Amanita muscaria) is ecologically very flexible and can sometimes turn up under aspens, as can some other poisonous species. So even in an aspen grove that looks safe at first glance, follow the identification rules.

Sources

  1. 1.Зерова М.Я. та ін. Визначник грибів України. 1979
  2. 2.Roger Phillips. Mushrooms (Roger Phillips)
  3. 3.David Arora. Mushrooms Demystified
  4. 4.Index Fungorum