Queensland's fire service head has reiterated hazard reduction burning is only one tool in the approach to addressing the growing bushfire risk amid criticism burn targets for the past four years had not been met.

Queensland Fire and Emergency Services commissioner Greg Leach said the window for hazard-reduction burns was shortening in Queensland and around the country, making it "more and more difficult" to achieve a targeted number of burns.

A December bushfire at Millmerran, south-west of Toowoomba, was one of a number of blazes which threatened communities in Queensland this fire season. Credit:QFES - Facebook

"Our fire season kicked off in July this year, which is unprecedented, and by August we were into significant fires across Queensland," he said. "The challenge we've got is that our seasons are changing."

Commissioner Leach said it was "highly likely" the next fire season would see even drier conditions and a burning program "significantly impeded" due to weather.