In the UK, 16-year-olds can drive a tractor on public roads if they have a full category F driving licence. This is because tractors are classified as "agricultural vehicles" and are often necessary for farm work, which is a common occupation for young people in rural areas.
The law permits 16-year-olds to drive tractors under certain conditions. For example, they are only allowed to drive a tractor that is capable of a maximum speed of 40km/h, and they must display an orange triangular slow-moving vehicle (SMV) sign at the back of the vehicle. In addition, they can only drive tractors on public roads for agricultural purposes, such as traveling between different fields or transporting crops.
It's worth noting that even though 16-year-olds are permitted to drive tractors on public roads, it's still important for them to receive appropriate training and supervision to ensure their safety and the safety of other road users.