I found what may be Johanna's maiden name Grilic. It was listed on her daughter Mary Catherine Vouk Ohman death record.
Mary C. Ohman, "Minnesota, Deaths and Burials, 1835-1990"
Name: Mary C. Ohman
Death Date: 23 Jan 1917
Death Place: Albany, Stearns, Minnesota
Birth Date: 1875
Father's Name: Valentiee Vouk
Mother's Name: Johanne Grilic
Indexing Project (Batch) Number: B02115-6
System Origin: Minnesota-EASy
GS Film number: 2138950
Reference ID: 13734