‘We can’t get it wrong again’ – a tree touted as a potential answer to New Zealand’s wilding pine problem has been being sold as something it’s not

A hybrid pine variety in huge demand has been labelled sterile and unable to spread without any evidence to support the claim.

With many southern farmers needing to be able to plant income-earning, carbon-sequestering tree blocks, the confusion over the hybrid’s status has highlighted a widespread desire for the Government to let sterile trees out of the lab and into production.

The relatively new Pinus radiata x attenuata hybrid is being snapped up due to its ability to thrive in the harsh conditions of the South Island high country. It is believed to have a lower spreading risk than many commercial forestry trees such as Douglas Fir and Pinus radiata, but is not sterile, according to government scientists and seed suppliers.

Next year’s crop of the hybrid is sold out and individual seedlings, until yesterday, had been listed at $13 each – compared to 90 cents each for standard Radiata pine – at Christchurch nursery Southern Woods.

Marketing manager Rico Mannall said this week, when informed of the discrepancy by Newsroom, that it was unclear how the incorrect ‘sterile’ labelling had occurred. It had been present before he started in the role, he said, but past purchasers of the hybrid, all based in Canterbury, would now be notified and corrections made to sales materials.

The hybrid had been sold for the past three years at around 2500 trees per year, mainly for trials, Mannall said.

Ngāi Tahu-owned tree seed supplier, Proseed, confirms the hybrid is not sterile. They say, however, that if a sterile tree could be made available it would be game-changer for the southern forestry industry.

“This hybrid is not sterile. Just like radiata pines, it produces serotinous cones that require high temperatures to open,” General manager Shaf van Ballekom told Newsroom.

Van Bellekom says the hybrid is classed in the same category as radiata pine when wilding spread risks are assessed. Proseed had not seen any spread so far, however, at high country planting sites.

“Sterile trees would be a great solution to help solve issues of wilding pine, but we understand the only possible avenue to undertake this for our current suite of plantation species would be through genetic modification technology. This is currently prohibited in New Zealand.”

Many say New Zealand’s legislation around gene editing – the process by which sterile trees have likely now been created ‘in the lab’ – are outdated and overly stringent.

Senior scientist at crown research institute Scion, Glen Thorlby, says the current regulations governing biotechnology, through the Hazardous Substances and New Organisms Act, were created in the late 1990s.

“We now have over 20 years of evidence regarding the use of these technologies that shows that with appropriate regulation they can safely be used and deliver economic and environmental benefits. The current regulation of gene editing in New Zealand is out of step with its regulation in most of the world. Gene editing was not developed at the time the HSNO Act was introduced and does not fit well within the current regulatory framework.”

As part of a Ministry of Business, Innovation and Employment and Forest Growers Research-funded programme called ‘Winning Against Wildings’, Scion developed gene editing (CRISPR) tools for use in producing sterile trees.

“We have used gene editing to knock out (inactivate) genes we think are essential for normal reproductive development. Without these genes the tree should not be able to reproduce,” Thorlby says.

The regulatory barriers to growing and testing trees outside, however, prevented evaluation of potentially sterility. This blocked the pathway for any sterile pine to progress and become commercially available.

Wooden it be good

Peter Weir is a past president of the NZ Forestry Owners Association and a member of a technical advisory group for the National Wilding Conifer Control Programme.

In his day job of 20 years, he is head of environmental performance and planning for Malaysian-owned forestry company Ernslaw One.

He was aware sterile trees had been successfully developed ‘in the lab’ by mapping genomes, or genetic information of existing species, and shares others’ frustrations that they cannot legally be field-trialled in New Zealand.

“Most countries don’t include gene editing in the definition of GMO – genetically modified. Most restrict the definition to transgenics (incorporation of genes from one species into another). Gene editing is just a way of doing what naturally occurs in nature as a mutation.”

The mutation of a sterile tree occurring in nature was a dead end for scientists as it couldn’t be reproduced without pollen or cones, Weir says.

He says new plantings of Douglas Fir – highly valued for timber in the south – had dropped dramatically due to increased public concern about wilding conifer spread.

“Producing sterile Douglas Fir was an obvious thing to do but we are frustrated by the regulations. Most politicians are scared to burn the political capital to have that debate so they kick the can down the road, not wanting to stir up a hornets’ nest.”

Forestry company, Ernslaw One’s environment manager, Peter Weir. Photo: Supplied

Gene editing had potential for helping with the expensive battle against other environmentally-destructive pest species like possums.

“It’s the same thing. It’s a debate New Zealand absolutely needs to have.”

A sterile forestry tree would likely also give 20 percent more growth and carbon sequestration as it would not need to expend energy into producing cones, Weir says.

He said the fir trees were largely being substituted by the Pinus radiata x attenuata hybrid due to its low-spread credentials.

“It’s way less fertile but I don’t think it’s sterile. People are typically planting five or six rows of that around the outside of a Douglas Fir plantation so you don’t get that edge spread.”

It was also popular with farmers for shelter belts due to its hardiness and snow resistance.

“It’s a moderately vigorous tree but you’re putting it on harsh sites. If you put it on the best sites it would probably bolt but we’re sticking it up high. You can’t stick radiata up high, they get wrecked by snow, that’s why farmers hate radiata as a shelter belt tree. Attenuata is far better. The branches won’t come down and wreck your expensive deer fence in a snow-storm.”

Wilding spread was low where stock were intensively grazed as they ate small seedlings. More survived on areas where fewer animals, either farmed or wild, were present.

He said if the total area of New Zealand’s dense commercial forest was compared with dense wilding forest, the former covers more ground, but when comparing land infested with wildings of any density, their proliferation exceeds that of the country’s considerable commercial crop.

In 2016, the government pledged $16 million over four years for the first phase of a national control programme for wilding pines. Budget 2020 allocated further Crown funding of $100 million over four years to expand the programme.

No GMO changes likely

The Government’s Environmental Protection Agency, which approved Scion’s application in 2010 to conduct gene editing trials in containment, says New Zealand continues to “connect and engage” in international discussions and agreements on GMOs.

This was through this country’s role in the Cartagena Protocol on Biosafety under the Convention on Biological Diversity. There are 172 parties to this protocol, according to Dr Chris Hill, EPA’s General Manager of Hazardous Substances and New Organism.

A spokesperson for the Ministry for the Environment said the Government was not looking to fully review the GMO settings of the Hazardous Substances and New Organisms Act, including the settings for field trials and full release.

“New Zealand has adopted a cautious approach to GMOs; however, our regulatory settings are comparable to the likes of the European Union.”

At present the ministry was only developing “policy options to address any unnecessarily restrictive restrictions on the use of genetically modified organisms within contained laboratory settings and for biomedical therapies.”

Will they or won’t they?

Phil Murray, the project manager for community-run Central Wilding Group, says a sterile tree would be a huge advantage but one whose benefits would be seen by the next generation.

In the meantime, he fears that with commercial forestry taking off there’s a risk we might be getting it wrong again by not having had the new attenuata hybrid tested over time for potential spread.

“We have to be very wary about making big decisions with some uncertainty about how successful it’s going to be. I feel like we’ve been here before … with radiata we were assured that it wouldn’t spread.”

Most wildings in Central Otago and Marlborough now costing millions of dollars to remove were radiata pine.

Field trials of the Pinus radiata x P. attenuata hybrids were established by Scion and Proseed, in the late 1990s.

These showed it to be tolerant of cold and dry conditions and to have good resistance to snow, according to a Scion publication. No reference is made in Scion’s reports to the tree being sterile or to any detailed assessment of its potential to spread.

Dr Heidi Dungey, the organisation’s science leader for forest genetics, was closely involved in the hybrid’s development and says Pinus radiata and Pinus attenuata hybrids are generally fertile, as they are two closely-related pine species, although these hybrids are not as fertile as P. radiata x P. radiata.

In her paper published in the NZ Journal of Forestry Science in 2010, Dungey says the attenuata hybrid was less of a spreader than some varieties.

The hybrid is often now planted instead of Douglas-fir at high altitude for that reason but Murray remains wary.

“We are marching flat out into forestry willy-nilly. We are expecting a vast improvement with the attenuata hybrid but we don’t know yet. They take 10 to 12 years before they start coning so you don’t know until after 10 or 12 years whether they will spread. We can’t get it wrong again.”

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