Saccharina latissima (Linnaeus) C.E.Lane, Mayes, Druehl & G.W.Saunders (BC/Ar/A)

This species has the common name “Sugar Kelp” for the sweet white powder that can form on the blade surfaces as they dry. This species is characterized by an entire blade (weakly digitate in some individuals) and has significant habitat-dependent variation in stipe morphology – from short and solid (Image A) to long and hollow (Image B) (sensu Saccharina longicruris (Bachelot de la Pylaie) Kuntze; McDevit & Saunders 2010). Some entire to slightly digitate individuals can take on the appearance Hedophyllum nigripes (Rosenvinge) Starko, S.C.Lindstrom & Martone, the latter distinct by the presence of mucilage ducts in the stipe (Longtin & Saunders 2015). Southern populations of Laminaria digitata (Hudson) J.V.Lamouroux can be nondigitate and manifest as squat looking representatives of this species, but differ by having mucilage ducts in the blade (Longtin & Saunders 2015). Molecular identification is best if absolute certainty is required.

A kelp of sheltered to exposed habitats, found typically from the low intertidal to 15 m subtidal, widespread and common with genetically verified records throughout BC, and from the Canadian Arctic to RI in the NW Atlantic (McDevit & Saunders 2010, Saunders & McDevit 2013, Longtin & Saunders 2015).

GWS013504.jpgImage A. Specimen with a short solid stipe from Burnaby Narrows, Haida Gwaii, BC (GWS013504).

GWS002505.jpgImage B. Specimen with a long and hollow stipe from Digby Neck, NS (GWS002505).