Appearance: Yellow green fronds, often with bright yellow thickened tips. The fronds have a midrib but no air-filled bladders.
Depth: Upper shore
Feeding: Spiral wrack is a producer. It makes its own food by photosynthesis. It has chlorophyll just like most land plants but the brown colour is due to extra pigments that allow it to absorb light efficiently.
Environment: Spiral wrack grows attached to rocks high up on sheltered shores using a holdfast.
Other facts: Spiral wrack survives the long periods it is out of water by the fronds curling as it dries so that there is less surface area. The fronds produce slimy mucus to keep them moist. The orange, swollen tips are reproductive bodies.
Classification: Spiral wrack is a member of the protoctista group, the brown algae.