Hartwig was a farmer and grazier by occupation and pioneered the first aerial sowing of pasture seed.
Hartwig began his political career as a councillor with the Shire of Monto (1961–1970) and was appointed chairman in 1964.
[1] Hartwig was never appointed to state Cabinet but had a notable achievement in fighting successfully to have Queensland Day officially recognised.
After leaving Parliament he became involved with the Liberal Party for a time and contested the 1988 South-Coast by-election for the fringe right-wing Citizens Electoral Council.
Upon his death in 1996, his former colleagues made a range of tribute speeches; the stories of Hartwig's career were frequently humorous.