A farmer escaped uninjured after his tractor caught fire pulling a silage trailer.
The incident happened on Monday afternoon on the A30 in Henstridge, Somerset.
Devon and Somerset Fire and Rescue Service sent two crews to the scene after the fire was reported at 1.16pm.
Firefighters worked quickly to extinguish the fire, to prevent it from spreading to the trailer which contained silage.
A spokesman for Dorset and Wiltshire Fire and Rescue Service said: "Two appliances were mobilised to reports of a tractor on fire. It was quickly established en route that the tractor was well alight.
"Crews extinguished the blaze using two breathing apparatus and two hose reel jets, and managed to stop any fire spread to the silage in the trailer.
"Responsibility was handed over to the police and highways agency to deal with hydraulic fluids and diesel on the road. Crews returned to station at 2.50pm."
No-one was injured.
The incident follows a warning from NFU Mutual of tinder dry conditions in the countryside.
The rural insurer is concerned that the current heat wave could lead to grassland and arable crop fires, putting lives at risk and costing millions of pounds in damaged crops and machinery.
“Following a very dry spring, the current heatwave means that huge swathes of land across the whole of the UK is at risk of fire – putting lives of people and animals at risk as well as destroying valuable crops,” said Tim Price, NFU Mutual Rural Affairs Specialist.
“With harvest due to start in a few weeks and the long summer school holidays on the horizon, we are making a plea to countryside dwellers and visitors to take extreme care to avoid starting a fire.”
“Matches and cigarette ends thrown down from cars are one of the major risks – but in the current conditions even a discarded bottle can concentrate the sun’s rays and start a fire.
NFU Mutual is urging farmers to make sure that fire extinguishers on combine harvesters are serviced before harvest start, and to make sure regular maintenance and cleaning to remove chaff is carried out.