Eged's Silverweed?

Silverweed is abundant on Islay - but some believe there are two distinct species.  This could be the maritime, salt tolerant one called Eged's silverweed (Argentina egedii) as it is growing close to the high water mark.  To tell Eged's from the common variety requires knowledge of the density of hairs on various bits of  silverweed anatomy.  As even botanists are divided over whether Eged's is an actual species, or simply a subspecies, it is not something that ought to keep us awake at night.
Silverweed used to be an important starchy food source - quite possibly very important to Scots  in the years BP (Before Potatoes). The roots can be dried and ground up into a sort of flour.  Apparently.  Those in the know claim it tastes like, er,  silverweed...