Common stinkhorn: what it looks like and where it grows

The common stinkhorn is one of the most unusual mushrooms in our forests. At first it looks like a white egg lying in the leaf litter, but within a few hours it shoots up into a long stem with a slimy tip and a pungent smell you can catch from far away. Watching it transform is a rare forest show.

Let's look at what the stinkhorn looks like at different stages, where it grows and how to recognize it.

The “egg” stage

A young stinkhorn looks like a white or cream egg 4–6 cm across, half-buried in soil or leaves. It feels springy, and inside there's a jelly-like mass and the beginnings of the future stem. This is the stage when the stinkhorn is easiest to confuse with other “egg-shaped” mushrooms, so it helps to cut the egg open: in a stinkhorn you'll see a greenish-olive layer under the skin.

The mature stinkhorn

In favorable weather the egg “sprouts” very quickly — sometimes within a few hours. Out of it stretches a white, spongy stem 10–20 cm tall with a bell-shaped tip covered in dark olive slime. That slime has a sharp smell of carrion that attracts insects — and they spread the spores.

Because of the smell, a mature stinkhorn is hard to miss: people often find it “by nose” before they see it.

Where and when it grows

The stinkhorn loves warm, damp broadleaf and mixed forests, parks and thickets with rich humus. It grows from June to September, singly or in small groups, often in the same spot year after year. Its look-alike, the dune stinkhorn, has a pinkish egg skin.

How to recognize the stinkhorn

Egg: a white, springy “egg” in the litter with jelly-like contents.
Stem: white, spongy, hollow, grows fast.
Tip: bell-shaped, with dark olive slime and a pungent smell.
Speed: few mushrooms grow this fast.

The mushroom is edible only at the young egg stage, with white, springy flesh; a mature stinkhorn with slime is no longer fit to eat. If you have any doubt about an “egg,” don't pick it — at this stage it's important not to confuse the mushroom.

Sources

“Key to the Fungi of Ukraine” (Kyiv, Naukova Dumka publishing house).
Phallus impudicus in GBIF, the Global Biodiversity Information Facility.
Phallus impudicus in MycoBank, the international fungal nomenclature database.
Phallus impudicus on Wikipedia.

Frequently asked questions

What does the common stinkhorn look like?

At first it's a white, springy “egg” in the litter, and then a white, spongy stem with a bell-shaped tip covered in dark olive slime quickly grows out of it.

Why is the stinkhorn called an egg mushroom?

Because when young it's shaped like a white egg, half-buried in the soil. The mature stem “sprouts” out of it.

How fast does the stinkhorn grow?

Very fast — from egg to mature mushroom sometimes within a few hours. It's one of the fastest-growing mushrooms in our forests.

Why does the stinkhorn smell like that?

The sharp carrion smell comes from the slime on the tip — it attracts insects that spread the mushroom's spores.

Where does the stinkhorn grow?

In warm, damp broadleaf and mixed forests, parks and thickets with rich humus, often in the same spot every year.

When does the stinkhorn appear?

From June to September, in warm, damp weather. The eggs are easiest to find after rain.

Is the stinkhorn edible?

Only the young egg with white, springy flesh is considered edible. A mature stinkhorn with slime isn't fit to eat.

How do you avoid confusing a stinkhorn egg with another mushroom?

Cut the egg open: in a stinkhorn, under the white skin you'll see a jelly-like layer and a greenish-olive embryo. When in doubt, the mushroom isn't picked.