Around 50 tonnes of manure was alight at a farm on Cattlegate Road in Potters Bar.
Four fire engines and 21 firefighters and officers have dealt with a manure fire at a farm on Cattlegate Road in Potters Bar.
Around 50 tonnes of manure was alight.
The Brigade was called at 0502 and the fire was under control by 0815. Fire crews from Enfield, Edmonton and Southgate fire stations attended the scene. Deep seated pockets of fire remain and relief crews from Hertfordshire Fire and Rescue Service have taken over the scene.