Mathis Anderson Minge

He was born 11.03.1837 in Tune, Østfold, Norway, nr 35 here:http://www.arkivverket.no/URN:kb_read?idx_kildeid=7499&idx_id=7499&uid=ny&idx_side=-314 They emigrated to America: http://www.arkivverket.no/URN:kb_read?idx_kildeid=7499&idx_id=7499&uid=ny&idx_side=-314 in June 1870. Margit Bakke kindly found his Naturalization Record from Polk County 1884/85, and record of land bought in Polk County in his name in 1889. After that, nothing. I would like to find more about their new life, and/or living relatives, and I am hoping that maybe someone might have an idea on how to go about it? Kari