Oskey Brothers was acquired by Northwestern Refining Company of St. Paul Park in the 1950's. Northwestern retailed gasoline through SuperAmerica, Laurie Gas, Trax Oil, North Star and Webb stations when in operation.
Norhtwestern was acquired by Ashland Oil in 1970. Ashland eventually changed the stations to SuperAmerica or sold them off.
I worked at the old Northwestern refinery and came across some of these patches there.