Hello!
I have Fjerdingstad in my family tree. My maternal grandmother's maiden name is Fjerdingstad. Her father was Lauritz (born 5 Mar 1847) and his father was Lars Larsen Rustand (born 10 Oct 1810). In case you don't know the men in Norway took the name of the farm they lived on as their last name. In that family alone we have Rustand, Foss and Fjerdingstad. Do any or those names sound familiar? Please let me know. Thanks!