Partner trees

Hazel

Hazel (Corylus), despite being a shrub, plays just as important a role in mycology as giant oaks or pines. Dense hazel thickets are a powerful mycorrhizal hub that attracts both the most expensive delicacies and the most dangerous mushrooms in the world.

12 species in the database.

Hazel's mycorrhizal partnerships and truffle treasures

In the «Key to the Fungi of Ukraine», M.Ya. Zerova classes hazel as an exceptionally active mycorrhiza former whose roots can support symbiosis with hundreds of forest mushroom species.

But hazel's greatest claim to fame, which Roger Phillips describes in detail in his guide «Mushrooms», is its mycorrhizal partnership with truffles (Tuber), underground ascomycete fungi:

1. Summer truffle ("Russian black") - Tuber aestivum: This delicacy, which grows underground, loves partnering with hazel on limestone soils.

2. French Périgord and white Piedmont truffles: In Europe, hazel seedlings inoculated with truffle mycelium are the foundation of commercial truffle orchards (because hazel grows and enters symbiosis much faster than oak).

Besides the underground delicacies, David Arora in «Mushrooms Demystified» highlights a whole range of capped mushrooms that grow among hazel:

- Milk caps (Lactarius): Hazel is often accompanied by the peppery milk cap (Lactarius piperatus) and woolly milk caps.

- Summer bolete (Boletus reticulatus): This netted (early) porcini sometimes turns up under large hazel bushes if there are oaks or hornbeams nearby.

- Brittlegills (Russula): A huge number of brittlegill species, especially ones with green and yellow caps.

But hazel is also one of the main partner trees of the death cap (Amanita phalloides). Dense hazel bushes give ideal shade and hold moisture — exactly the environment this deadly poisonous species loves.

Hazel as a substrate for saprotrophs

Old, dead hazel branches rarely support large wood-decay fungi (like polypores or oyster mushrooms) because of their small diameter. But they are a substrate for dozens of species of tiny discomycetes (ascomycetes) that look like little cups or saucers on rotting wood.

Questions and answers

Why are truffles so often grown under hazel rather than oak?

Hazel is a shrub that grows much faster than oak. Its root system develops rapidly, and the first truffle harvest on a planted orchard can come as soon as 5-7 years after the mycorrhized seedlings go in, whereas oaks need decades.

Can you find a death cap under a hazel bush in your garden?

Yes, if the soil conditions are right and the roots have been colonized by the mycelium. The death cap (Amanita phalloides) can form strong ectomycorrhiza with hazel. So always be careful with any mushroom that resembles a brittlegill or an Agaricus if it has come up under hazel.

Which mushroom gives off white milk and grows under hazel?

That's a milk cap (Lactarius), most often the peppery milk cap or the fleecy milk cap. These mushrooms are classic mycorrhizal partners of hazel. When damaged, they release an acrid white milky juice. They are conditionally edible and used only for salting after prolonged soaking.

Do slippery jacks grow under hazel?

No, slippery jacks (Suillus) are obligate (strictly bound) mycorrhizal partners of conifers such as pine or larch. You won't find them under broadleaf trees, hazel included.

Sources

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