in taxon kelp oarweed Laminaria digitata is a large brown alga in the family Laminariaceae*, also known by the common name Oarweed. It is a tough, leathery, dark brown seaweed that grows to two or three metres. The holdfast which anchors it to the rock is conical and has a number of spreading root-like protrusions called rhizoids.*Laminaria digitata* occurs in the north west Atlantic from Greenland south to Cape Cod and in the north east Atlantic from northern Russia and Iceland south to France. It is common round the coasts of the British Isles except for much of the east coast of England. atlantic kombu laminaria digitata sea tangle tangle Laminaria digitata requires discussion