Knotted wrack - Ascophyllum nodosum Scientific names: Ascophyllum is composed of two greek words: askos, which is a waterbottle made of leather, and phyllon, meaning leaf. Nodosum, of latin origin (nodosus), means ”to be covered in lumps or knots”. Other english names: Sea whistle, yellow tang and Norwegian kelp.

Knotted wrack     Other names