A team of Kiwi firefighters in Australia say the workload is "huge" and Australian crews have no end in sight.
Five crews were deployed to a forest fire at Charleys Forest, east of Canberra, last week. The blaze covers nearly 65,000ha.
Crew leader Ken Keenan said the heat and different terrain made the conditions extremely difficult, but they were able to provide some reprieve to local crews.
"The other teams, they've been working for weeks on end and we're here to give them a break. A bit of rest, some R n' R, because they're gonna be at this for quite some time."
He said the work was arduous, and their firefighters must be extremely fit.
"In a typical day, we might drive two hours for a start, and then walk another hour or two just to get to the fire line."
Strike team leader Bruce Janes praised the team for their "military-like" focus.
"It tends to be 14-16 hour days and you've just got to be very disciplined. As soon as you get back, you almost run through the shower and get to sleep."
Only 10 per cent of the team were paid firefighters, he said, and the volunteer efforts were outstanding, considering people had to leave paid work and their homes to help out.
"We've got a guy whose wife's sick at the moment, someone else is having a drama at home, and they're just awesome. Just an outstanding crew, no issues at all, super disciplined and hard-working."
The teams were patrolling a fire break between the fire and unburnt vegetation, but Keenan said there were still surprises.
"Yesterday, we thought we were going to a moderate spot fire but we got there and it was pretty intense. So the plan changed pretty rapidly."
Janes said although the physics of fire was the same, the flames travelled differently on Australian terrain and native vegetation.
"There's these very quick direction shifts of the fire, and they're pretty big fires, up to 20-metre flames, just depending what it's running through."
More than 170 New Zealand firefighters have been deployed to Australia since October, and Janes said the worst wasn't over yet.
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"They'll be in drama for months yet. Victoria's only just kicking off. The rain will be awesome for finishing some of the fires that are going quiet. But, those fires that are about to start with the very next lightning strike - that symptom of a continental climate is dry lightning - those are your next fire-starts.
"Your long-term drought and your forest death across Australia, just means more drama to come."