Although Judith Collins spent her childhood driving tractors on the farm, she's under no illusion about her ability to master one of today's machines.

"They're enormous ... extraordinarily expensive equipment and dangerous in the wrong hands," National's leader told The Country's Jamie Mackay.

On yesterday's show Deputy Prime Minister Winston Peters reiterated his previous comments that anyone could drive a tractor, and that they were more difficult to manoeuvre when he was 10 years old.

Collins disagreed.

"You know what I just thought it was ridiculous when he said that. I mean I was driving a tractor when I was a kid on the farm and a teenager as well – but that was a long time ago – those tractors then were little Massey Fergusons."

As a result of Peter's comments, Mackay dared him to drive a silage harvester, an idea that has resulted in many farmers sending in photos of machinery for the Deputy PM's challenge.

Collins said she was not keen to take part in the challenge, having recently visited agricultural contractors in Te Awamutu and seeing their equipment.

"My word, those machines are bigger than they used to be when I was a kid."

The Opposition Leader was further deterred after she was offered a photo opportunity inside one of the vehicles.

"I looked at that ladder [and me] trying to get up there ... and I thought, that's about three stories high."

"Just think of the dreadful Photoshops of me climbing up that ladder. I thought, oh no i don't think so – it could be even worse coming down," she laughed.

Meanwhile, Collins addressed National's "gone by lunchtime" comments on the Government changing freshwater rules yesterday.

While the party's agriculture spokesman David Bennett actually said "they're gone by lunchtime," Collins admitted she shouldn't have said it again.

"I sort of [was] a little shocked so I repeated it, but I shouldn't have."
Some elements of the Government's freshwater regulations had come under fire, especially around winter grazing.

"Some of the regulations seemed to be across the county, even though, as we know, farming is very region-centric in terms of how you operate ... the things like the weather and the soil types," Collins said.

Dairy farmers had been "bashed around by the left for a long time" when in fact, they'd been doing well environmentally, according to Collins.

"They've fenced off 98 per cent of their waterways, which is the distance from Auckland to Chicago and back again, and they've done all that in the last 15 years at their own expense."

"If you look at the miles and miles of riparian planting that have gone on. Between 2010 and 2015 the average dairy farmer spent $90,000 on upgrading effluent management."

"Well I'd put that against some of the local councils in the urban areas which have some of the filthiest waterways you could ever come across."

It was important not to buy into the "rhetoric of the far left," who Collins believed were saying they "liked farmers at the moment" because tourism was going through a difficult time.

"I don't like that whole dirty dairying thing and that picking on farmers, which after all is not just farmers - it's the whole of provincial New Zealand we're talking about here."