Dillisk or Dulse is a dark red seaweed which can be found in the intertidal zone, an area of the shore between high and low tides. It has translucent flat fronds and a small round holdfast that attaches it to rocks or to other seaweeds. It can grow between 25 and 45 cm in length. It is eaten by periwinkles, shells and other sea creatures. People eat dillisk too.

In Mayo St. Columba’s monks used to harvest it 1400 years ago. Nowadays it is still harvested by hand during the spring and summer months and spread on netting to dry in the sun and wind. When the leaves are covered with sea salt, the dillisk is ready for cooking. It can be added to salads, sandwiches, soups, chowders, breads and cakes providing the dish with a crisp taste of sea salt. It can be also eaten dried as snack.

It is rich in essential vitamins, sea salt and minerals such as potassium, manganese, iron, zinc and calcium.

Its botanic name is Palmaria palmata, in Irish it is called Duileasc.