When Neil Hardman saw a bushfire menacing his home on Melbourne's rural fringes this week, he feared the worst.

The huge Mickelham-Kilmore fire, the state's largest, was raging for 50 kilometres, destroying homes and other property as it went.

But when Mr Hardman returned on Tuesday, he found his home had been spared from the flames.

And the volunteer firefighters who saved the property had spared the time to leave a note expressing their regrets that they had not been able to find Mr Hardman's horses.

The note, from a CFA firefighter named Frank Amoroso, is titled: "We fought hard!"

"We did the best we could... put out fire in house and moved your car. Could not find horses, sorry," the note reads.

Mr Hardman says he lost his shed but fire crews ensured his house was spared.

"When we first saw the shed going down, we thought, that's our life gone, and then we looked across and saw the house and you forget about the shed straight away and you go onto the house and you say, well let's save the house," Mr Hardman said.

"So, we went straight back, got the CFA down here.

"One of the fire guys left a lovely little note on the dash saying how hard they worked trying to save the house and animals and stuff like that, and the note is absolutely brilliant; it's just saying, you know, he left his name and his telephone number and the guys need medals; they really do; they're just brilliant; they really are."

Sorry, this video has expired Neil Hardman praises firefighters' efforts

Mr Hardman says the shed which was lost contained old farm machinery with sentimental value, including his wife's father's old tractor.

"We've been here 12 years and you know, you sit here and you think, 'This is never going to happen to me and never going to happen to us,' and Mother Nature has its own way of finding a result," he said.

"You know, I don't want to stay here in case another flare-up comes through and we lose the house. We'll reassess that when the time comes."

Emergency warnings downgraded

Firefighters began to gain the upper hand on the state's fires on Tuesday, with emergency warnings scaled back and no towns under immediate threat by late afternoon.

But watch and act warnings remain for many areas across the state.

The blazes have so far destroyed 34 houses and damaged another 20 across the Latrobe Valley, East Gippsland and Kilmore areas.

CFS divisional commander Greg Murphy says the fires could burn until March.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Listen Duration: 4 minutes 3 seconds 4 m 3 s Rachael Brown's report from the bushfires Download 1.9 MB

"The fires are burning into very, very difficult terrain for us to work in," he said.

"The hills, the valleys, the rocky areas will make it extremely difficult to extinguish completely; we will need to remain vigilante for the next six to seven weeks for this fire alone."

The Mickelham-Kilmore fire has now burned through more than 23,000 hectares.

Three CFA volunteers have been injured, including one last night when a tree fell on a fire truck.

In the east, the fire burning in the Hazelwood open cut mine is far from under control, but is not affecting local communities.