Adder's tongue fern

Master of deception

Adder's tongue fern © the City of Helsinki materialbank, Saana Kemppi

The adder’s tongue fern (Ophioglossum vulgatum), which grows almost exclusively in coastal meadows in Finland, is difficult to spot. However, you might find this elusive plant in Kallahdenniemi and Uutela, where it is most prevalent, in the early summer.

The plant’s appearance is deceiving; the stem that looks like an inflorescence is actually not an inflorescence nor a stem, but rather a two-part frond. The actual stem of the plant is a vertical rhizome hidden in the soil.