The Snaelda is a hugely popular Icelandic Salmon Fly pattern. Icelanders have taken this fly pattern to every great salmon river in the world and replicated its success wherever they have fished.  The Yellow and Green is a good early season Salmon Fly when the fish are fresh in from the sea.  It works particularly well in rivers carrying a green tinge such as the Gaula in Norway or the Grand Cascapedia in Canada.