Reb--I'm talking from first-hand experience. I've lived in the fire zones of CA, AZ, NM, CO, and most of the other western states. I'm not a firefighter, but I know guys who have worked for CDF, etc.
Prescott is NOT someplace you just hoist a Cat D-9 and start plowing shit. I'm talking 20-30 degree slopes. Or worse. Throw the wind on top of it and you've got a nightmare on your hands.
The fires, believe it or not, can burn UNDERNEATH you even as you think you're digging it or plowing the fuel and pop up behind your ass. This is why the firefighters tell residents in threatened areas to get the hell out if their homes are threatened, cause more often than not, it's not just their homes that are at risk, no matter how much clearance there might be between them and the brush/forest.
These guys were trying to save AN ENTIRE TOWN. Most of that town is now GONE.