This iconic kelp species, aka the Sea Palm, barely needs introduction (Image A). Although they would never be confused in the field, this species is like a compact version of its close ally Nereocystis luetkeana (K.Mertens) Postels & Ruprecht. Postelsia is typically confined to the mid to upper intertidal on rock/mussel habitat in exposed areas. The golden to olive brown thalli consist of a relatively compact hapteral holdfast, a long hollow and smooth stipe, which bears a tuft of grooved and marginally dentate fronds (Images A & B). Individuals grow in gregarious colonies where found, and can reach up to 60 cm in height.
We have genetically verified records from central CA in the south to central Vancouver Island, BC. You cannot mistake this species for anything else in our flora.
Image A. Cluster of individuals growing in the upper intertidal near Bamfield, BC.
Image B. Individuals have a compact hapteral holdfast, smooth stipe and long grooved fronds with dentate margins (mid intertidal, Point Lobos State Reserve, CA; GWS021498).