Bracken is a fern-type plant. It has branches with many small leaves, known as fronds. Bracken has underground 'runner' roots which run along under the ground and new shoots will grow up from them. Bracken is poisonous and has lots of ways of surviving, which is why it is so successful.

Brackens are found on all continents except Antarctica and everywhere except deserts, but they are most common on poor soils and moorland. Brackens do not have seeds or fruits, but have spores which devlop on the underside of the leaves (fronds).

The fronds may grow on stems to over 2m tall. In places where the winters are cold (such as Nortehrn Europe and North America) the bracken dies back in autumn, the fronds turning brown. Elsewehre it is evergreen.