Green’s Dictionary of Slang

(US) a farmer, a rustic.

c.1850		F.M. Whitcher Widow Bedott Papers (1883) 76: I wanted old Dawson’s wife to see [...] I’d got a pardner ruther above a common plow-jogger, such as hem is.
1938		Amer. Mercury Oct. 248: Did he ever talk with taxi-drivers, gas-monkeys, grease-balls, gandy-dancers, soda-jerkers,...pearl-divers, bindle-stiffs, nut-knockers, or plow-jockeys? [HDAS].
1942		Berrey & Van den Bark Amer. Thes. Sl. §391.3: rustic, bumpkin, plow jockey.
1946		‘Sl. of Maladjustment’ in AS XXI:3 Oct. 238/2: plow jockey. A soldier unable to march, who marches with one foot in the furrow.
1950		Goldin et al. DAUL 161/1: Plow-jockey. A farmer; farmhand; a rustic.
1960		Ruth I. Aldrich ‘Misc.’ in AS XXXV:2 158: plow jockey (farmer).