I remember the hassle my sister had, to deal with her daughter's horse when the 2003 fires here in Canberra burned through the agistment paddocks. (She was damned lucky not to be killed, and her calls for help to my brother and me didn't get through, as the mobile phone network was swamped/taken over for emergency purposes.) She was fortunate that her house wasn't burned, though the suburb was threatened, and that she had a grassed backyard to put the horse in (though it was so small the horse was spooked, put his foot in the swing set, ate all the roses, etc - more of a comedy moment, that). They got the horse there, later, by daughter riding, sister leading (and no, her daughter was safe at home at the fire time). Lucky it was only a few miles. She did lose her new car - the fire swept over it, at the road above the paddocks, and though it was drivable (all the windows shattered), inspection showed it was totally fritzed and unsafe.
So many people now in Victoria won't have had any of that good fortune, and if their horses did escape the fire they'll be in desperate need of help. The horse-riding fraternity does a lot of networked helping, but money for feed and fencing eases things.