The export of kauri logs as Maori carvings is closely monitored and is not being used as a loophole, Primary Industries Minister Nathan Guy says.
Northland conservationists have complained large logs are being dug out of wetlands and sold overseas. The ecologically sensitive wetlands are badly damaged in the process, the Far North Protection Society says.
Swamp kauri can be exported if it is a finished or manufactured product, or a personal effect.
Whole or sawn salvaged swamp kauri stumps or roots can be exported with a milling statement and export approval. Swamp kauri logs may not be exported, either whole or sawn.
But with swamp kauri fetching large sums overseas, particularly in China, the society says logs were being passed off as Maori carvings and sent out of the country. It has complained that the Ministry for Primary Industries and Customs have turned a blind eye.
Labour has called for exports of kauri to be stopped, but Mr Guy said they needed to be signed off as finished products.
"I have seen some photos where some fantastic-looking kauri swamp logs have been carved and they are going to be an amazing feature for our country [in places where] they are destined for. So we manage it very, very closely," Mr Guy said.
Far North Protection Society chairwoman Fiona Furrell said some of the carvings were little more than scratchings. "The depth is only 10cm - that is just a scratching on the surface of a log."
Documents she received from the ministry under the Official Information Act showed officials had concerns about one carving in 2013.
The exporter, New Zealand Forests, a major player in the swamp kauri industry, stated the carving would go to a Chinese showroom to showcase Maori culture.
"I find this rather unconventional because of its raw appearance," a ministry official noted.
An expert the ministry consulted said the carving was unusual in a traditional sense because of the shallow carving and sparse detail, but could not rule out it being a legitimate contemporary carving.
Yesterday an employee at NZ Forests' Auckland office said the piece in question was a genuine Maori carving, and exported as such.
In five years the company said it had exported only two kauri carvings, the one in question to China and another donated to a culture exchange project in France.
A ministry spokesman said assessment focused on whether a product was in its final form, and was ready to be installed or used without further machining.
"In all three cases of temple poles exported in the last 12 months, there was a clear record of their intended use of the products as temple poles."