Fires can be detrimental to farming systems but many pastures are resilient and can recover.
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The extent of the damage to a pasture depends on how hot the fire burnt, the pasture type, soil fertility and seasonal conditions before and following the fire.
Research officer with the NSW Department of Primary Industries, Suzanne Boschma, works in the field of rangelands and tropical pastures.
"The intensity, or how hot a fire burns, and its effect on pastures falls into three categories," Dr Boschma said.
"Cool to moderate burn, hot burn and very hot burn.
"In a cool to moderate burn, most dead plant material is burnt leaving only a small amount of unburnt residue, whereas in a hot burn the ground is charred and bare, and all dead plant material is burnt."
"In a very hot burn all plant material is destroyed including soil organic matter and surface roots," she said.
"The soil surface is virtually sterilised and water infiltration can be reduced because the soil surface is baked."
Different fire intensities have varying effects on pasture types.
"Where a fire burns cool to moderate, seeds of some species will be destroyed but those which seed below the ground will survive and perennials will also survive," Dr Boschma said.
"However, in a hot burn, young perennial pastures and those weakened by drought and other factors will likely die," she said.
Pastures already weakened by drought may not survive fire as well as they would in a normal year.
Sarah Baker, pastures development officer with DPI said a number of steps can be undertaken to regain pasture productivity after a fire event.
"Wait for significant rainfall to see what comes back," said Ms Baker.
"Alternatively, water a small section to see which perennial species respond and which annual grasses, legumes and weeds regenerate.
"Fertilising will help the pasture recover faster; the pasture has been weakened and productivity will be reduced for around 12 months.
"Controlling weeds to reduce competition for resources is also vital to helping pastures to recover," she said.
"Annual forages are useful for providing quick feed for livestock, ground cover and controlling weeds in preparation for sowing perennial pastures in one to two years' time."
If most of the pastures on a property have been inadvertently lost to fire, it is an opportunity to re-think an individual's integrated farm plan, including pastures and fencing layout.
"Take the time to plan paddock sizes and boundaries based on features such as soil type and aspect," Ms Baker said.
"Prioritise which paddocks to re-sow, especially with perennials and seek advice from your local agronomist."
