A 4WD track featuring steep slopes, a waterfall, boulders and pools of water is one of the attractions at this year's National Fieldays in Hamilton.

Foul weather and wild winds only slightly dampened today's opening of what is touted as the Southern Hemisphere's largest primary industry showcase, which runs through to Saturday at Mystery Creek.

A few of the smaller tents were blown down overnight, but there was no serious damage and the event opened on time at 8am.

Among the events is 500m dirt track that features a 45-degree slope, a boulder mountain, a log climb and an 800mm-deep lake that suffered from the overnight deluge. Professional drivers have been hired to take people through the course in new Ford Rangers.


"The lake was pretty deep this morning, until we got a through vehicles running through it," said Ford NZ marketing manager Chris Masterson.

"Luckily our tent, stand, and course survived the big winds last night. Some other stands and smaller tents were blown down. There was a bit of carnage here."

He said the course, which is free, was in an enclosed area. Children under 8 years old could not participate because of safety belt reasons, and those aged between eight and 17 had to be supervised with an adult.

The Ranger should also get slightly airborne as it rolls over a series of half-pipes.

"It's a dirt track with lots of obstacles. It will take the vehicles to their full capability," Mr Masterson said.

"It's under controlled conditions. The worst thing that could happen is getting stuck. It's pretty wet and muddy but it seems to be coping really well so far."

Organisers hope that more than 125,000 people will come through the gates over the next four days, to look at the latest dairy farming technology and other showcases from the 900 companies and organisations taking part.

Primary Industries Minister Nathan Guy, speaking at Fieldays, highlighted the political undertones of the annual KPMG Agribusiness Agenda, which noted uncertainty around a potential change of Government across the 150 industry leaders surveyed.

"The general election is just around the corner and this agenda highlights that industry leaders are weary of how the election result may impact on their economic momentum," Mr Guy said.

"As this independent report states: 'Election 2014 is the most significant in decades for the primary sector'."

He said the Ministry for Primary Industries had an extra $17 million from this year's Budget, with a focus on biosecurity and food safety.

"We are also beefing up the border with new staff, more dog detector teams, and new x-ray machines."

On the web: www.fieldays.co.nz