Bleach Weed    Prionitis lyallii



This reddish to yellow-brown seaweed is found in the intertidal and shallow subtidal zones sometimes inhabiting small tide pools at the mid-tide level.  It is distinguished from other reddish seaweeds by its tough, elongated and flattened, 6 to 8 inch blades with small leaflets emerging from the sides.  In addition it emits an antiseptic smell when crushed, like bleach or iodine, which is thought to be a deterrent to grazing animals.


It can be found from British Columbia to Baja California in Mexico.  In more exposed areas the leaves are redder whereas they tend to turn yellowish in quieter waters.  This difference is thought to be due to the higher level of nutrients brought to the plant where water movement is high.  However, as seen in the photograph, both types of leaves can occur together.  


The bleach weed is one of many members of the major group of seaweeds called the red algae with around 600 species in our area.  The other seaweeds are the brown algae (around 150 species), many of which are called kelp, and the green algae, such as sea lettuce, with around 130 species.  Each group has evolved along a different pathway and therefore are not related.