Page "Tractor" Paragraph 48

Until the beginning of the 1960s, tractors had a single register of gears, hence one gear stick, often with three to five forward gears and 1 reverse.

Then, group gears were introduced, and another gear stick was added.

Later, control of the forward-reverse direction was moved to a special stick attached at the side of the steering wheel, which allowed forward or reverse travel in any gear.

Nowadays, with CVTs or other clutch-free gear types, fewer sticks control the transmission, and some are replaced with electrical switches or are totally computer-controlled.