environment

Unwanted organism sold as native plants

The New Zealand Transport Agency ordered locally occurring native plants for 140 hectares of new planting as part of the Kāpiti expressway project. What it received included an Australian pest and trees from as far away as Northland.

Approximately 21,000 plants had to be ripped out.

The sole plant supplier for the project was Kauri Park Nurseries. It is the last remaining native plant nursery of scale in New Zealand, shipping around nine million plants a year. Other suppliers have gone into receivership or closed down in what has been described as an environment of “undercutting to nothing”.

It wasn’t Kauri Park’s first time shipping the Australian tree considered a weed to restoration projects where eco-sourced plants had been specified and paid for. According to Kauri Park, however, the mistakes were due to external seed collectors, including a "local guy" possibly connected with local iwi and an “older guy” from Waiheke Island.

Eco-sourcing is more frequently becoming a contractual obligation for restoration projects. It means sourcing seeds from what grows locally in the area. It’s part of a practice to ensure the biodiversity of an area is retained. Mixing varieties of plants can have unintended effects. New introductions can swamp local varieties by replacing them completely, or by crossing with them and creating hybrid swarms.

Ideally plant material is eco-sourced from a range of trees in an area. Seeds are preferable to cuttings, and seeds from a number of trees are preferable to seeds from just one tree to ensure there is genetic variation.

Done correctly, eco-sourcing can play a part in preserving local variations of plants, some of which, such as mānuka, may have important properties, or play a role in eco-systems which is not yet fully understood.

Kāpiti’s Mackays to Peka Peka expressway project

It was one of the North Island’s biggest planting projects. Surrounding 18 kilometres of the $630 million four-lane road are approximately 800,000 supposedly eco-sourced native plants.

Kauri Park’s website talks of its pride at being sole plant supplier and the effort undertaken to eco-source seeds: “To help protect the biodiversity of this unique region, the seeds for the M2PP [Mackays to Peka Peka] project were all eco-sourced – seeds were sourced from plant material from the region which it was to be replanted back into, retaining the genetic footprint that has evolved over many generations.”

During a routine audit of the project in March an eagle-eyed ecologist spotted suspicious looking plants. Samples sent for identification to botanist Peter de Lange revealed kunzea linearis from Northland had been used. The plant originally requested for the project was kunzea ericoides and this was updated before planting to kunzea robusta, a variety identified as coming from the Kāpiti area.

“What they tell you is what you believe.”

Emails released to Newsroom under the Official Information Act call the presence of the Northland kunzea a “mystery”.

A March project report said visits were made by to the sites the seeds had been collected from. No parent plants which matched the supplied plants were found at the sites. The conclusion in the report was “foreign seed” had been mixed in with local seeds.

In the March report it was agreed the plants would be removed and replaced at no cost.

A September 17 email showed a further audit had found the kunzea which was supposed to be removed was re-sprouting. Urgent removal was recommended before the plants started flowering in October.

Kauri Park’s managing director Phil Wearmouth said the errant kunzea seeds the nursery grew were not collected by its own staff and came from a “local guy in that area”.

“We had to engage with the local iwi, they wanted to do some collection. Some of the seed we were supplied for the likes of that there wasn’t actually even ours. We don’t know the actual trees.”

He said the issue of the incorrect seeds was raised with the seed supplier after the incorrect plants were spotted in the audit and “they can’t give us the location of where they got it.”

The September audit of the Kāpiti expressway project also found Tasmanian ngaio. Similar in appearance to New Zealand ngaio, the Australian variety is listed as an unwanted organism by the Ministry for Primary Industries.

In areas where it has been planted it has crossed with the New Zealand ngaio and created large areas of hybrids.

For Kauri Park nurseries, it is the second time the nursery has sold the Australian invader for a New Zealand natives project. Over 8,000 were also sold for the restoration of Rotoroa island in the Hauraki Gulf in 2008.

“We used an older guy in Waiheke, and I believe going back to those ngaios, they were cuttings, not even seed grown. That was the first we were given that stock and I guess even then the difference between Tasmanian and New Zealand [ngaio], that was probably the first time it was flagged as an issue in New Zealand.”

He said the Tasmanian ngaio found in the Kāpiti project came from an external supplier used by Kauri Park “to top up the supply chain”.

“Once again some of those are cutting grown stock. Some of those once again would be external suppliers.”

He said any problems would “absolutely” come from these external suppliers.

“What they tell you is what you believe.”

Kauri Park has taken on the responsibility of removing and replacing all the incorrect plantings at the Kāpiti expressway. Wearmouth said he was not aware of other projects where Kauri Park had supplied incorrect plants.

The nursery now had an in-house eco-sourcing facility which was a "large investment". It uses GPS locations of the trees from which the seeds are sourced and barcodes to provide traceability.

“When Kauri Park have full control of a project we can guarantee the seed source.”

“Every other week we are hearing about native plant nurseries closing down or struggling."

He pointed out less than 1 percent of roadside planting has been shown to be incorrectly eco-sourced and “to see perspective 1 percent of a contained roadside planting pales into insignificance when compared to the plague across the country of regenerating pine trees in our native forests … should we put a stop to forestry in this country?”.

The native nursery industry

The One Billion Trees project and a greater focus on eco-sourcing comes at a time when New Zealand’s native nursery industry is struggling.

New Zealand Plant Producers Incorporated (NZPPI) is an industry body representing plant growers. It's funded by membership fees which are based on the turnover of its members. Chief executive Matt Dolan said: “Every other week we are hearing about native plant nurseries closing down or struggling. This is happening at a time when they need to be gearing up to meet the increasing demand from the Billion Trees programme and other initiatives.”

A competitor to Kauri Park, the Native Plant Nurseries went into receivership in April. It had been in business since 1961 and at the time of the receivership employed around 35 staff.

Other native nurseries such as Oratia Native Plant Nursery are shutting shop due the owners wishing to retire and no buyers to be found willing to take on the business. According to the owner, while costs have risen the price of plants is the same as it was in 1990.

Industry insiders mention the price of plants delivered to the site for some large tenders have dropped to between $1 to $2 per plant. Unrealistic timeframes, the scale of projects and procurement processes which favour a single point of contact for hundreds of thousands of plants over dealing with a group of nurseries have also been mentioned by insiders as issues for the industry.

Dolan suggests price competition is coming from community nurseries.

“One of the biggest challenges is that that native tree nurseries often have to compete with subsidised and volunteer nurseries with unrealistically low prices.”

With nursery closures comes the loss of decades of knowledge.

The head of the Te Uru Rākau, the Minstry for Primary Industries forestry arm Julie Collins spoke to Newsroom in September. A partnership fund aimed at helping nurseries is to be created.

"We are looking to use that to support some of the enablers of tree planting. How do we support nurseries to stand up?"

She said the agency has been in discussion with NZPPI.

“We don’t want to start creating a playing field where we supported one nursery and they undercut everybody else and everybody else goes to the wire and goes bankrupt.”