Hi Barbara,
Was Erick Ericson born on the Sovde farm in Norway? As you have probably found the Norwegians last names depended on the first names of their fathers. Many of those who immagrated to the US took on the name of the farm. My husbands family did this. I know for a fact there are Sovdes in Mpls, MN (my husbands' family) Greenbush,MN, North-West Iowa and Everett, WA. Although the others are no relation they did start from the Sovde Farm.
Hope this will lead you somewhere.