Forest Hill blaze burns 20ha of farmland near Pardelup Lagoon before being contained on Sunday

Firefighters are patrolling Forest Hill in the Shire of Plantagenet on Monday to mop up after a fire burnt 20ha of bush and farmland on Sunday afternoon and required aerial support to contain.

Emergency services received reports of a “column of smoke” near the Pardelup Lagoon at 1.15pm.

Thirteen crews from Forest Hill, Porongurup, Rocky Gully, Denbarker, Middle Ward and Mt Barker bushfire brigades attended the scene near Muir Highway and Pardelup Road.

Two waterbombers were sent to assist the on-ground firefighters.

The blaze was contained four hours later at 5.15pm.

A Department of Fire and Emergency Services spokesperson confirmed more than 20ha of farm and bushland had been burnt as of 3.20pm on Sunday, but no structures were damaged.

The blaze did not spark a bushfire advice alert.

The cause has not yet been determined and firefighters remain on scene mopping up.