A global citizen science platform
to discover, share and identify wildlife
The fronds are flattened, with straight edges and a mid-rib. This species often grows with the fronds twisted into a spiral. During the summer you may see bumpy v-shaped swellings with distinct rims at the ends of the fronds. These are its reproductive structures. Its fronds can grow to 70cm long. This species looks similar to toothed wrack, but can be separated because its fronds have smooth edges. (http://www.nhm.ac.uk/)
Spiral wrack is found on the upper part of the shore.
Spiral wrack curls as it dries in order to conserve moisture. People used to believe that if they soaked their feet in boiling water that contained the reproductive parts of this seaweed, it would cure their corns.