A surburban kiwifruit grower whose illegal orchard in Auckland was destroyed last week by the Ministry for Primary Industries came to MPI's attention only after trying to sell fruit to the exporter Zespri.
The Ministry for Primary Industries says it found about 100 plants at the property, which had been grown from seeds illegally brought in from China and planted in 1999.
The seeds were never declared nor went through any biosecurity checks.
Kiwifruit Vine Health chairman Peter Ombler said the industry found out about the orchard only when the owner tried to sell fruit from it.
"Zespri asked some questions at that point about the correct documentation, import permits and the like, and as I understand it, the person said that they had the correct documentation but they didn't have it with them.
''So subsequently the contact was made with MPI regarding some sort of restrospective arrangement whereby they could have the plant material approved."
But Mr Ombler said MPI testing also revealed there were several viruses in the vines.
"Plant viruses per se are a completely normal thing as I understand it. I think all plants have plant viruses in them. Some of them beneficial is my understanding.
''So that in itself isn't particularly hair-raising but there was, as I understand it, you know a couple that they ... hadn't been seen before so, and once again that's quite normal, there are thousands that are unidentified in New Zealand.
"So that in itself is not unusual either but from the point of view of the kiwifruit growers we want to take a conservative attitude in this area. The last thing you want to do is have a problem later that you could have done something about at the time."