Allot depends on the type of bush and the amount of trees and other bushes in that area the obviously the denser the forest then your burns are to be conducted on a regular basis due to the amount of leaf matter dropped by the trees etc at the station it was a rotational system with our scrub on site 1100 hectares on about a 2 year cycle for various zones obviously we had sparse areas where it would be around 5 yearly +- season dependent.

CALM our land management authority is given X amount to burn yearly I think last year in the southwest they had something like 200,000 hectares ear marked to burn off but due to the season they only accomplished 15% of that and in the past there has been some burns that got out of hand with property loss etc so they have to ensure everything is correct and the risks minimal.
That film we watch on the Australianicon crew they actually caught on camera a fire tornado it was not you small cockeyed Bob but a full blown funnel of fire going through the tree tops like Dantes Inferno it was a chilling sight and something I hope never to encounter in the flesh.