The Country Fire Authority says there were no injuries when a header caught fire north of Nhill on Wednesday night.
A spokesman said four brigades rushed to Yanac at 6.40pm, managing to get the fire out quickly so that it did not spread to the surrounding grass.
He said the fire, reported to be on the corner of Berontha Baker and Beatties Road, destroyed the header.
The Yanac crew remains on the scene, which has been declared safe.
The Mail-Times has contacted Nhill police for more information.