Adder's-tongue fern

Adder's-tongue Fern

┬ęBruce Shortland

Adder's-tongue fern

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Scientific name: Ophioglossum vulgatum
The adder's-tongue fern is so-named because the tall stalk that bears its spores is thought to resemble a snake's tongue. An indicator of ancient meadows, it can be found mainly in southern England.

Top facts


Height: 10-20cm

Conservation status


When to see

June to August


Adder's-tongue fern is an unusual fern that grows in grasslands and meadows, on hillsides, along woodland rides and on sand dunes. It usually appears between June and August, spending the rest of the year underground as a rhizome. It is considered a good indicator species of ancient meadows and can be found alongside common spotted-orchids, quaking Grass and devil's-bit scabious.

What to look for

The adder's-tongue fern has a bright green, oval and upright frond, with a single, tall spike that bears the spores protruding from it. Mostly, it only has one frond, but sometimes has a pair.

Where to find

Localised distribution, mainly in southern England and not very common.

Did you know?

There are two other closely related plants, the small adder's-tongue fern and the least adder's-tongue fern, both of which are much smaller and rarer, and are only found at a few sites around the south-west of England.