Gudmund Persen (Pedersen) Nedrebø left Norway between 1900 and 1910. Since he was born in 1891, chances are he left Norway after he turned 18, but before the 1910 census.

I think this is Gudmund, 18 years old, leaving Norway for Saskatchewan, Canada, on 20 Feb 1909:

http://digitalarkivet.no/cgi-win/webcens.exe?slag=visbase&am...