Imported plantings at the centre of a national biosecurity scare have started to be destroyed, although one group of industry members has challenged the directive and lodged a judicial review.

The issue involved apple and stonefruit plant material imported from a specific United States facility since June 2012 that could not be confirmed as being free of pests and diseases, the Ministry for Primary Industries (MPI) announced on July 31.

About 47,500 plants and small trees at 32 nurseries, importers and growers nationally have been affected.

Eight Central Otago stonefruit orchardists were affected — seven who had test trees for new varieties and one who one had significant plantings of a new variety and would need to destroy those trees, Summerfruit New Zealand chief executive Marie Dawkins said after the MPI announcement.


She said last week no more information on the Central Otago orchardists or their plantings was available, and could not confirm if any were part of the group of five industry members who had challenged the MPI directive to contain and/or destroy plantings at the centre of the scare.

The group had lodged a judicial review with the High Court at Wellington seeking to overturn the MPI decision, or at least extend the timeframes "in order for MPI to gather and consider all relevant facts", a joint statement said.

The statement said the MPI directive was "based on a paperwork issue", and there was no evidence of "an actual biosecurity risk".

No major pests or diseases had been found on affected apple plant material, but more testing was required for lower-risk apple pests and diseases, and for affected stonefruit material, an earlier MPI statement said.

No sign of disease in Central Otago has been announced.

An MPI statement last week said so far 24 owners had opted to destroy their plant material, and more than 200 plants had been destroyed nationally.

No breakdown on Central Otago growers was available "for privacy reasons", the statement said.

When asked about the judicial review, an MPI spokesman said: "We understand this is difficult for affected growers, nurseries and importers. MPI is confident with the decisions we have taken and our processes. We have carefully assessed all of the risks associated with this plant material. Our decisions are about protecting New Zealand and our wider horticultural industry from biosecurity risks. We can't comment further as the matter is before the courts."