The Minister for Primary Industries is defending the export of kauri logs as carvings, saying it is a good way to promote the country.
Northland conservationists say the logs are being illegally exported under the guise of carvings and the Government is doing nothing about it.
The Far North Protection Society said that, despite their complaints, its members were still seeing massive logs dug from ancient wetlands, heading south on trucks to be sold overseas.
It said both the Ministry of Primary Industries (MPI) and Customs were ignoring a cynical abuse of the law.
Minister Nathan Guy said he was aware of their concerns but his ministry was keeping a close watch.
He said the logs needed to be signed off by MPI and have an export certificate.
"They are finished products, I have seen some fantastic-looking kauri swamp logs being carved and they're going to be an amazing feature for our country and an international country that they're destined for. So we manage it very, very closely."
Mr Guy said New Zealand had been processing kauri logs from swamps for about 30 years domestically and the export market was growing.
However Labour's spokesperson for conservation, Ruth Dyson, said the Government should ban the export of kauri full-stop.
"It has been raised on several occasions, it's been dismissed previously, I think now that it's been picked up so strongly in the media the Government won't be able to ignore it."
She said it did not matter whether the kauri was sold as carvings or not - it was time for exports to stop.
Kauri log trade flouts law, says group
Kauri miners pay Far North landowners hundreds of dollars a cubic metre for the timber they unearth, which can fetch thousands of dollars in China and other countries.
The Far North Protection Society said the multi-million dollar trade was not only illegal - it was destroying an entire ecology of wetlands and fragile dune lakes.
The chair of the group, Fiona Furrell, said despite repeated complaints to MPI and customs, trucks were still rumbling south, each with one massive log on board, masquerading, however improbably, as carvings.
"Recently there were three seen going out from Awanui in one day," she said.
The kauri logs are being carved at Dave Stewart's depot in Awanui, north of Kaitaia, at the complex known as the Ancient Kauri Kingdom.
Mr Stewart said he carved some of them himself, and agreed some of the carving was superficial. He said he had supplied just three of the carved logs in the last two years to clients in China.
But Ms Furrell said MPI and Customs were turning a blind eye.
"The logs are just logs, with a few scratchings on them," she said.
"They're less than 10 centimetres deep because the prime object is the log so you don't want to damage the timber, because the value of the log on export is in the timber, not in the carving."
Ms Furrell said great slabs of swamp kauri were also being exported as table tops and countries from Asia to Poland were processing them, gaining the added value and jobs that should be New Zealand's.
Fragile wetlands bear the brunt of mining
The conservationists' primary concern is what the swamp kauri industry is doing to the environment.
From Ahipara to Houhoroa. the ecosystem is a complex series of wetlands that filter into tiny dune lakes set in a landscape of peat and sand.
Much of the area was worked over more than 100 years ago by kauri gum-diggers.
But now, to extract the kauri, miners must first drain the wetlands - and dig much deeper than the gum-diggers ever did.
Lake Ngatu resident Sarah Fountain said, since that happened on farmland opposite her house, the once-pristine lake had been polluted by runoff.
"Because it was all going, all this peaty, swampy water, into Lake Ngatu, and the deterioration in Lake Ngatu over the past two or three years, it has been absolutely incredible," Mrs Fountain said.
"It was pristine. It was one of the best in Northland, and now you can't see your feet when you're up to your knees in water."
Local farmer and naturalist Kevin Matthews said the change in water quality had affected the kuta - a golden reed that grows in the dune lakes, and is highly prized by Maori weavers.
"When the water becomes murky, the reeds can't photosynthesise - and they die back, and that in turn affects water quality," he said.
Mr Matthews said Northland Regional Council issued resource consents for kauri extraction only if it deemed the wetland did not have plants of significance.
"But what happens is the landowner ring-drains his wetland; the significant plants die off, and it's then pronounced to be no longer of significance, and it can be mined for kauri."
Mr Matthews said the kauri extraction that's taken place in recent years has changed the water table in many parts of the north.
"It's not something that once done, can be put right," he said.
"The regional council comes in after the fact with ad hoc measures - when it's told for instance that a dug-up area is draining into a lake. But by then the damage is done. And they haven't forseen it or anticipated the consequences of messing with the hydrology.
"In another 10 to 20 years, we may have lost these lakes forever to pollution and algal blooms."
'All we're asking for is that the law be obeyed'
Auckland geologist and conservationist John Allen said the kauri miners had in many cases broken through the hard pan that kept groundwater close to the surface, sustaining the wetlands and lakes.
He said the entire ecosystem was now at risk and it was inexplicable that the authorities had done so little to prevent that, or monitor the swamp kauri industry.
Dr Allen said the Far North environmental group had complained repeatedly to customs and MPI about kauri log exports, providing photos and other evidence - and had been promised investigations.
But so far, he said, that had come to nothing. "All we're asking for is that the law be obeyed, and applied."
MPI documents seen by Radio New Zealand show staff had concerns about the eligibility of one particular export log last year, which had shallow patterns carved into it, splashes of red and white paint, and what appeared to be a large, smiley face at the top.
A Maori artist consulted by the ministry said it could not be considered a traditional Maori carving, but might be considered a contemporary one.
MPI forestry and land management director Aoife Martin told Checkpoint it had investigated two kauri logs carved by Mr Stewart at the depot in Awanui and sent to China.
"I'd describe those as carvings on a log... The check showed who was purchasing them, for what purpose, and there was some good correspondence and information exchanges between the Chinese customer and the New Zealand company."
“On Tuesday, June 16 we broadcast a story (and subsequently published it on our website) about the contention of environmentalists in Northland that the Ministry for Primary Industries was failing to ensure that swamp kauri exports complied with the requirements of the Forests Act 1949.
The story referred to Oravida (and one of its directors David Wong-Tung) as a kauri wholesaler. We accept that Oravida is not a kauri wholesaler and we did not intend to suggest that Oravida and Mr Wong Tung were involved in the illegal export of swamp kauri logs or that they had exported swamp kauri in breach of the Forests Act.
Radio New Zealand unreservedly apologises to Oravida and Mr Wong-Tung for its error and any suggestion they have acted unlawfully.”
Listen to Aoife Martin