How do mushrooms reproduce?

Plants reproduce by seeds, animals give birth to young, and fungi have chosen their own path — spores. These are microscopic “seeds,” and a single mushroom releases millions or even billions of them. Let's look, in simple terms, at how this works and how a new mycelium grows from a spore.

What spores are

A spore is a tiny cell, thousands of times smaller than a poppy seed. It's for the sake of spores that a fungus grows a fruiting body at all: its whole cap is a spore “factory.”

Spores ripen on the underside of the cap, in the hymenophore:

• in pored mushrooms (porcini, slippery jack) — in tiny tubes;
• in gilled mushrooms (honey fungus, brittlegills) — between the gills;
• in puffballs the spores ripen inside and burst out in a cloud when the mushroom matures.

How spores get around the forest

Ripe spores fall from under the cap and are carried by the wind — sometimes for kilometers. Other routes help too: spores cling to animals' paws and foragers' shoes, and insects and snails carry them around.

That's why mushrooms turn up in the most unexpected places: it's enough for just one spore out of billions to land in suitable conditions.

How a mycelium grows from a spore

Once it lands in moist, warm soil or wood, a spore germinates into a thin thread — a hypha. The threads branch, intertwine, fuse with threads from other spores and form a mycelium — the actual body of the fungus.

The mycelium grows in the soil for years, building up strength, and when moisture and warmth line up, it shoots up fruiting bodies. The cycle closes: the new mushrooms scatter spores again.

Why fungi are so successful

Reproducing by spores is remarkably effective. A single large mushroom releases billions of spores, so even if only a tiny fraction germinates, the mycelium still spreads. Thanks to this, fungi have lived on Earth for hundreds of millions of years and are found almost everywhere.

By the way, that's exactly why there's no point fearing you'll “destroy the mushrooms” by cutting them — more on that in the article how to pick mushrooms: cut or twist. And as for why fungi aren't plants or animals at all — see our piece are mushrooms plants or animals.

Sources

• Spore on Wikipedia.
• Fungi on GBIF, the global biodiversity database.
• Fungus reproduction in Encyclopaedia Britannica.