Clearly one of Michigan's "Good Roads" governors, Green enthusiastically supported expansion and upgrading the state highway system during his two terms as chief executive (1927-1930). He was the "inventor" of the yellow no-passing line, first used in Michigan, which eventually became a standard safety device on highways everywhere. He was one of the early proponents of a bridge across the Straits of Mackinac and ordered the first survey to determine the feasibility of a span to link Michigan's two peninsulas. A successful industrialist, Green's public life prior to his election as governor included 12 years as mayor of Ionia and a stint as chairman of the Ionia County Road Commission.