BioDiversity Thought Leader

Going Native

Last month I called for a bloody big new forest in New Zealand: 1.3 million hectares by my reckon. Could be more, could be less – but this is the right ballpark for a meaningful reduction to our net greenhouse gas emissions.

The report, Our Forest Future, prompted plenty of discussion, but one issue stood out: a lot of New Zealanders have had a gutsful of Pinus radiata.

I’ll save the pros and cons of radiata for another day. Here I’ll discuss some alternatives; specifically, the potential for native trees as commercial forests. Because by bringing new native forest into the mix – for commercial planting as well as conservation planting – we can plan for a forest future that New Zealanders might actually want.

Common opinion will tell you that natives grow too slowly to be profitable. But the reality is more complicated.

“It’s like a craft beer versus a Tui beer,” says forester Clayton Wallwork. “[Native forest] is more expensive to establish, but you’re going to get a higher-quality timber, a higher-quality product, as a result. You’re also going to have a whole lot of other benefits – to the community, to the environment.”

Wallwork is involved in a project called “Our Forests, Our Future”, led by Tane’s Tree Trust. The intention is to get a better handle on the economic potential of native forest, not only for timber but also for environmental benefits.

The project is ongoing, focused on demonstration forests of beech in the South Island and totara in Northland. Trials won’t be complete until 2018 – but early signs are positive. They’re looking at the processing, the timber grading, the pricing; and Wallwork says of the totara that “it’s already a lot higher than what you’d get for radiata.”

You might wonder: how can anyone do field trials on trees when they take so long to grow? Won’t it take decades to get results?

The Northland Totara Working Group, established in 2005, looks at totara that self-regenerated on farmland. As long as landowners left the seedlings to grow to maturity, these decades-old trees can serve as approximations for how totara would grow if planted deliberately. Since 2007, the Working Group has pruned and thinned these forest plots, to see how they respond to best forestry practice.

Dr David Bergin, who also works on the project, is an expert on totara, a wood prized for its durability and workability. He’d like to see a more nuanced national forestry, where we’re “matching the appropriate species to the appropriate site… blending in a diverse multi-use forestry with existing land uses.”

Our commercial forests are currently 90 per cent Pinus radiata. Bergin says: “With radiata, you’re dealing with a high volume, low value, commodity; so, you’ve got to grow that on an industrial scale.” He’s worked alongside Māori landowners in Northland managing large pine plantations, mostly shipped to China as cheap unprocessed logs. He says “they’re getting a peppercorn rental; they’re on steep difficult country with poor soils; they’re hardly making anything out of it after trucking costs – so it’s marginal even for radiata.” He says there’s a real hunger for alternatives.

Forestry research centre Scion is also engaged in indigenous forest research. One recent study found that kauri, along with mānuka, made positive economic returns in six areas around Northland (see graph below). Indeed, in four of the six areas, the investment case for kauri was superior to, or comparable to, Pinus radiata, both pruned and structural-grade.

The study estimated the land expectation values (LEVs) for different kinds of forest, then calculated incomes by factoring in costs of planting, harvesting, transport, and annuity. The areas where radiata performed best—South Hokianga, Central Taitokerau, and South Kaipara—were all areas where markets were closest and transport costs low. But, averaging across them, the income for kauri was estimated to be 4.7 times higher than structural-grade radiata pine over a 60-year period.

Land expectation values (8% discount rate) of Pinus radiata (prune and structural grade) alongside native species. Source: Scion, 2014.

Land expectation values (8% discount rate) of Pinus radiata (prune and structural grade) alongside native species. Source: Scion, 2014.

So, if native trees aren’t such a bad investment, why aren’t we growing them?

For decades, native forestry has been held back because reliable information is all-too-rare and unreliable information is all-too-common.

One of the researchers on the Scion study, Greg Steward, tells me: “It’s about getting us away from that anecdotal information that’s been promulgated around the countryside since the days of Kirk and Cheeseman.”

When Steward studied kauri for his Masters degree at University of Canterbury, he found far higher rates of productivity than anyone expected, occasionally getting close to Pinus radiata on optimal sites. Since then he’s helped to develop the Kauri Calculator, an online tool for landowners which predicts future production and income for kauri.

People are taking a second look at natives, he says, “because now we’ve got data. You can deny anecdotes until the cows come home, but you can’t deny data.”

Misinformation goes back as far as early European settlement. Under the Waste Lands Act of 1854, native forests were defined as precisely that – as “waste lands” – and treated accordingly. The common view was that one blade of grass was worth more than two trees.

Not everyone went along with this. By the late 1800s, says Steward, “various folk were starting to question how we were managing our forests and our native timber resources.” At the time, we were not only cutting down ancient forests to export timber overseas, we were also starting to import foreign timber to meet local demand. Yet New Zealand chose to undertake large-scale planting of exotic pine throughout the 1920s to boost domestic supply. In 1919, forester Sir David Hutchins observed: “for reasons which have never been satisfactorily explained, it has been thought to replace the valuable native forest of New Zealand by artificial plantations of exotics – a quite unusual proceeding in forestry”.

Some early field trials for natives – although showing promise – were sidelined in this rush to plant exotics. Later trials were conducted on public land, often at high altitude or on land recently clear-felled. Unsurprisingly, these sub-optimal sites produced sub-optimal results. Some historical data, Steward says, no one knows its origins, nor therefore its reliability.

A 17-year-old kauri stand near Tauranga with stems of 34 centimetres diameter at breast height. Recent density analysis of this stand indicates growth rate is not affecting wood density. Source: Steward et al., 2014. Republished with permission of Greg Steward.

A 17-year-old kauri stand near Tauranga with stems of 34 centimetres diameter at breast height. Recent density analysis of this stand indicates growth rate is not affecting wood density. Source: Steward et al., 2014. Republished with permission of Greg Steward.

Meanwhile, Pinus radiata has benefited from decades of government and industry research. Landowners can easily estimate their return-on-investment for radiata, as well as carbon sequestration rates. Selective breeding has also made it a “super-species”, fast growing and resilient to disease. While there’s no reason that native trees couldn’t also be optimised through selective breeding, that work hasn’t yet been done.

To put it bluntly, New Zealand forestry is suffering from a bad case of “path dependency”. In other words, our decisions in the present are constrained by decisions from the past. The historical dominance of Pinus radiata makes its continued dominance a foregone conclusion.

It’s this hurdle that Wallwork, Bergin and others hope to overcome with the “Our Forest, Our Future” project.

“There’s knowledge out there,” says Wallwork, “but no one can see a demonstration forest that’s been done, that has the books open to show what the potential revenues are.”

Bergin adds: “This project is about getting blocks of reasonable scale, demonstrating best practice, and dispelling those misperceptions out there.”

It’s not that Bergin is dead-set against radiata: “It seems to occupy a gap in our flora that we don’t have an equivalent to. It’s very plastic, grows on a range of sites, it’s very forgiving, it grows really fast initially.”

But he wants to see “multi-species, multi-age, multi-purpose forestry as a mosaic across a landscape, for which I think native forestry has excellent potential to blend in with those other land uses.” He reckons that once we go down this route, “this is where the real foresters come out of the woodwork – if you know what I mean – where they have to understand forest ecology, not as a crop but as an ecosystem.”

But that transition will require effort. To break the path-dependency of Pinus radiata, there needs to be more research, which means more research funding. It’ll also require market development, particularly educating New Zealanders to choose sustainably grown native timbers, rather than import foreign timbers which aren’t always sustainably harvested. It’ll require industrial-scale nurseries and economies of scale to bring down the price of establishment. Finally, where local rules prohibit the felling of all native trees, even those that were planted deliberately, we’ll need to find regulatory solutions that enable sustainable native forestry without endangering conservation efforts.

So what about climate change?

Evidence shows that natives, on average, don’t grow as quickly as Pinus radiata, and so sequester carbon more slowly.

Granted, there’s room to improve the growth rates of natives through selective breeding. There’s also room to be smarter about which trees go where: the right native tree on the right site with the right aftercare will likely defy many people’s expectations. Wallwork tells me that mānuka on the East Coast can compete with radiata in terms of sequestration. But this will likely only narrow the gap between the early growth rates of natives and exotics like radiata and eucalyptus, not close the gap entirely.

Predicted carbon sequestration rates on average sites. Source: Tāne’s Tree Trust, 2014.

Predicted carbon sequestration rates on average sites. Source: Tāne’s Tree Trust, 2014.

Yet there are other things to consider.

A lot of what forests sequester isn’t in the wood, but in the biomass below the ground or on the forest floor. Kauri forest has one of the highest biomass carbon densities in the world. Although this below-ground biomass is excluded from conventional carbon accounting, from a climate perspective, it’s still carbon that’s locked out of the atmosphere.

Another issue is resilience. For example, kauri, once established, is highly resistant to drought, indeed even has a competitive advantage in dry conditions (that’s why kauri often clusters on ridgelines). It is also, like totara, a sturdy tree that isn’t susceptible to wind throw. So, if global warming means more droughts and more violent storms for New Zealand – which is what the Royal Society predicts – then there’s good reason to plan more diverse forests, rather than gamble on a monoculture that’s uniformly vulnerable to the same hazards.

There’s also questions over long-term strategy for permanent forests. Bergin notes that, although some exotics have a growth advantage in early decades, this diminishes over successive decades because the growth of radiata eventually plateaus at around fifty years. Once we’ve reached, say, one-hundred years, though, we’re talking about mature native and exotic forests that are storing comparable volumes of carbon. But the native forests may well be more sustainable over the long run, because of their intrinsic value and more diverse income opportunities. Wallwork notes that, when carbon forestry was first floated, all sorts of ridiculous plans were hatched for densely spaced forests of radiata, unthinned and unpruned, which would have aged into hazardous and unmanageable forests with little value beyond their stored carbon. Such forests, as you can imagine, would be first in line for land use conversion.

What are we to learn from this?

Our forest future doesn’t need to be a future of Pinus radiata alone. There are alternatives on the table. And that’s just as well, because as long as landowners have a choice over what they plant, then many landowners won’t want to plant radiata pine (at least not without handsome incentives). Given that the majority of land available for future forest is privately owned, climate policy needs to take seriously the preferences of people, whether its their aesthetic preferences, cultural values like kaitiakitanga, or concerns over biodiversity and wilding pines. A native tree in the ground will always sequester more carbon than a fast-growing exotic that never gets planted at all. This is why, in the Our Forest Future report, I called for a principle of “appropriate diversification”.

Fortunately, native trees are not only a feasible option, they’re sometimes the more profitable option, especially when landowners pick the right tree for the right site. That doesn’t mean we should only plant native trees with commercial purposes in mind. Native tree planting for conservation projects, for habitat restoration, for permanent forest sinks, and for riparian planting should be a part of the picture too – the bigger the better. But anyone who relies on their land as their principal source of income needs to make ends meet. Native planted forests – sensibly managed – can strike a balance between favourable economic returns and favourable environmental outcomes.

And if that isn’t green growth, then I don’t know what is.

About the author

Dr David Hall

Dr David Hall

David Hall is a freelance writer and researcher who recently completed a doctorate in political theory at the University of Oxford. He has contributed features and columns to the New Zealand Listener since 2008.

27 Comments

  • Hi David, Great. I hope you’ve seen native species forestry guide we did for Northland more than a decade ago. We did others too. Cheers, Di Lucas

    • Hi Di, I’ve seen your work all around the place, but not sure if I’ve come across a piece on Northland specifically. Please share if you’ve got a link! Cheers, David

  • Solid work! It’s madness that New Zealand has sold off all its native timber and now has to use treated pine for everything. It’s like NZ sold off the family cow, and then wondered why the beans weren’t magic after all…

  • Andy – NZ has not sold off its native timber – 24% of NZ is still in Native Forest (largely DOC controlled). The rules that protect our Native trees simply make it difficult to produce native timber. Radiata was planted specifically to replace NZ’s native timber.

  • It is somewhat ironic that the largest native planting project on the Kapiti Coast is being undertaken as part of the work on the new coastal highway. Lots more native planting will take place as part of the Transmission Gully project. So this shows that when there is a will and some money attached to this large scale plantings can take place. On the Kapiti Coast lots of smaller scale planting is taking place on various restoration sites – mainly undertaken by older members of the community. But wouldn’t it be great if we could figure out a way to fund larger scale planting – that would also employ younger people struggling to find work. There are plenty of sites on the coast including regional parks. Maybe a carbon tax with the money going to such a scheme?

    • Cheers for your thoughts Paul. The great thing about the commercial native forestry discussed in the article above is that, in the right circumstances, it’s just a good solid long-term investment. You only need to find long-term investors, because it’ll turn a decent profit. The restoration planting you’re talking about does need to be funded, though. A carbon tax is definitely one option. For forest of the right scale, the Permanent Forest Sink Initiative is another option, which almost functions like tax-and-transfer (albeit with uncertainties around price). I reckon there’s other options out there too – hopefully something for another article!!

  • Deciduous trees such as Ash, Maple, European beech etc are well proven in the manufacturing industries, they do not require special permits and return annually far more biomass in the autumn than any NZ native this is also sequestering carbon, I grew up not far from Oxford the hedgerows (windbreaks) were mainly hazlenut which served as feed when trimmed in the winter and all the chiltern hilltops were planted with mixed woodlands, Beech, Larch, Ash etc ensuring water retention, the leaves composting ensuring fertile hillsides and valleys. NZ could learn a thing or two about sustainable farming with this technique. I have farmed much longer in NZ and have limbed and milled Totara and planted ribbon wood for shelter however these are not as well known overseas or in my humble opinion as good for the environment as deciduous trees

  • Near the town centre of Upper Hutt there is a woodlot of totara which look to me to be of millable size, though of course they can grow much bigger. They were planted in memory of Norman Kirk after he died.
    About 30 years ago I last looked at Turner’s Cottage, a 19th century pioneer’s hut at Rai Valley. At that stage the unpainted hand-hewn totara cladding looked well-weathered, but still apparently sound.
    In Nydia Bay in Pelorus Sound 30 years ago there were totara (possibly matai) logs in the water. On historical conservation grounds DoC required these unrotted logs from early logging days to be left. This led me to wonder if totara cladding could be preserved for a very long period with regular doses of salt water. With long applicators one might not need to use scaffolding. The walls might look awful but 7.4Mj per square metre of embodied energy of water-based paint would be saved.

  • Another great article David. NZ should be negotiating for underground biomass to be included in carbon trading schemes, not just for forestry but for all forms of farming. Sequestration via tree planting and biological farming represents a major economic opportunity for NZ and probably the only short term global opportunity to stay under 1.5 degrees.

    • Cheers Cimino – great article. Thanks for sharing! A commission on forest – or perhaps even land use more generally – would be a welcome initiative. What I do know is that the Institute for Forestry is currently undertaking a Forest Policy Project, which draws on the wisdom and expertise of folk around the country. So that’s something to look forward to. There’s such a need for strategic long-term thinking in this space – but it sounds like I don’t need to convince you of that!

      • Most kind David. I am a very recent student of forestry, brought about by the dire need for reforestation of the Mahurangi catchment to address its greatly elevated sediment accumulation rate. A quest for more cost-effect plants and establishment methods led me to Dr David Bergin, and the incomparable Jaap van Dorsser—a very deserved Queens Medal there, if there ever was!

  • Excellent articles, particularly the comprehensive and inclusive perspective. Are you aware that the NZ Institute of Foresters is promoting a NZ Forest Policy?
    There is a lot in what you say that I want to endorse, particularly your comments on radiate; it will grow virtually anywhere. By comparison most trees, exotic and native, are very site specific and so require in depth knowledge and experience in assessing site characteristics and the needs of the various species. NZ has some wonderful farm foresters who, as primarily land managers, think in terms of the relationships between various land uses and not simply uses in isolation one of the other. Their question is “what can trees and woody vegetation generally contribute to the overall resilience and viability of the land I manage?” This is the question a forest policy needs to address. And we might need to accept the costs of putting vegetation back where its presence benefits us all by providing valuable ‘ecological services’. As you say, forests provide far more than wood. A forest policy needs to address the role of forests in sustainable land management and not just the role of forests in supplying industry.

  • It is interesting to note that the very large and efficient American Hardwood industry (which exports large volumes of prime, slow-growing timber) gets its raw material from thousands of small privately owned woodland lots. When surveyed on why they grew the trees, owners put financial returns as third priority, behind such criteria as aesthetics and amenity! There is no reason why we can’t do the same. We do not have to always ‘think big’ and only consider large scale mono-crop plantations, which are so vulnerable and ugly. If the Americans can make such a successful industry out of it so can we.

    • Cheers David – I couldn’t agree more. It would be a strange model of psychology that sees us making decisions *solely* on profit maximisation. Of course, financial considerations are crucial for landowners to ensure that they don’t bankrupt themselves. But beyond that bottom line, there’s all sorts of trade-offs to make with other values: aesthetic, cultural, or prudential. And why not make more nuanced choices when landowners – or their grandchildren – have to live with them! This is one way to force a distinction between profit-maximisation and utility-maximisation, where the former is only about cash in the hand and the latter is about well-being more broadly. I reckon green growth makes most sense when it aligns with the latter (and actually it’s only fairly recently that mainstream economics started confusing the two).

  • Here is a real life example of trying to get a local native re-afforestation project underway. Perkins farm on the south end of the Kapiti Coast was bought by NZTA as part of the Transmission Gully Motorway project. It is around 400 hectares. Much of it is steep and erosion prone. Fencing is in poor condition. It would be ideal if around 200 hectares was left to revert back to native forest – with a bit of help along the way. Local restoration group Nga Ururoa did a report on re-afforestation – various agencies such as DoC, Kapiti Coast District Council or Greater Wellington Regional Council dont want any additional land -so how does one get the land into an ownership structure that suits this purpose and fund such a project?

    https://ngauruora.files.wordpress.com/2015/06/perkins-farm-restoration-28-november-final.pdf

  • Given that approximately 20% of the surviving Kauri in New Zealand are presently dying or already dead from Kauri Die-back Disease, it seems highly improbable that Kauri will represent the future for timber growing in this country!
    Unless a solution is found, and quickly, it is highly possible that the death rate will extend to 100% of our remaining Kauri. Hardly the basis for a healthy timber industry – first we need to solved this extremely devastating disease, otherwise all discussion about Kauri is entirely theoretical.
    There are no major Kauri districts that are now free of this disease, The Coromandel was thought to be clear but two forests have been found with the disease in the past year.
    Northland, Waitakeres, and Great Barrier Island all have substantial areas where the disease is rampant, with no solutions evident. This is killing trees of all ages.

    • This is a really thorny question and I can’t pretend to be an expert in this particular area. (If any experts want to jump in, though, then please do!) That said, there’s a few general points worth making…

      First that all tree species have potential diseases, including Pinus radiata. See here There’s even a disease called red needle cast, which belongs to the same family (Phytophthora) as kauri dieback, and has resulted in serious losses on some sites. So the potential for disease is a factor in all commercial forestry, not only kauri, and foresters simply have to weigh up their odds.

      Secondly it’s in the nature of genetics that some trees will be more resistant to kauri dieback than others. This lays the foundation for selective breeding of trees that are less likely to die from the disease. There are precedents for this in fighting other Phytophthora diseases, such as selective breeding of the Port Orford Cedar. It’ll be crucial, therefore, to grow any commercial kauri from trees that appear to be resilient against the disease, which would also expand the “genetic bank” of resistant kauri for conservation planting also. What’s missing is further research – and research funding – into these possibilities.

      Thirdly and relatedly, it’s in the nature of research funding these days that funds are more likely to be available if there’s an economic incentive involved, like commercial prospects. I’m not saying that that’s a great state of affairs: I think there should be more research funding available to conservation causes. It’s also not entirely true in this case: Government already funds research on kauri dieback, although there’s always the question of whether they’re investing enough. But the point is that the existence of a strong case for economic opportunities could make more research funding available to pursue solutions like selective breeding.

      http://www.scionresearch.com/__data/assets/pdf_file/0005/43907/HTHF_Kauri_dieback.pdf

      http://www.kauridieback.co.nz/media/6572/the%20science%20behind%20pta.pdf

  • One area you haven’t covered in your article is how to address the risk for someone who has planted a crop of native trees with an expectation that they will harvest them, that they can’t. There is considerable fear among some would-be “alternative species” foresters that they will get to harvest time only to find that they have accidentally created a Significant Natural Area or the like. This problem has already arisen for the riparian setbacks that plantation foresters create. These grow native species, and some district plans then regard them as SNAs, for which no damage – no matter no harvesting is allowed.
    It reflects the dichotomous approach to forests and forestry in NZ.
    Exotic production = industrial forest = OK to chop it down.
    Native trees = precious = don’t touch.
    Until people have some sense of security that they will be able to harvest – be it kanuka, totara, beech or others – this is another live issue to solve. You need to develop a method that gives legal security to differentiate, for our native trees:
    a planted area with an intent to harvest – and the right to harvest, from
    a planted area with an intent that it stays as is.

    • Thanks Chris – your point is a very valuable one. I think that’s exactly right – that there needs to be a sense of coherence, transparency, and purpose to rules in this area. That’s precisely why I’ve argued that we need a national conversation and a rethink on landuse/forest policy. Personally, I think along similar lines to you, that new native forest that has been intentionally planted should be free from the restrictions that protect our conservation forests; and instead should be managed under regimes guided by permanent canopy cover and/or kaitiakitanga values, so that our future forest is economically sustainable too. I talk a little more about that here: in this report – http://pureadvantage.org/news/2016/04/22/our-forest-future/

  • Kia ora David, you mention about the pros and cons of radiata, please can you direct me to any good authoritative summaries of the relative merits? I’m looking to advocate for investment in native-based projects rather than radiata plantation, but would like to use some evidence-based summaries. Any assistance gratefully received. Thanks, Phil

    • Kia ora Phil, great to hear! Yeah there’s tough trade-offs in these decisions. Below are some good overviews of the “ecosystem services” of planted forests (which generally means radiata forests) in NZ. I would also strongly recommend looking into transitional regimes, because depending on your circumstances, you could plant a nursing crop of fast-growing exotics like eucalypts or paulownia which raises your overall carbon sequestration rate, provides an interim revenue stream, and eventually allows slower-growing natives to enjoy the shelter before they take over. Mark Belton discusses this briefly here: http://www.listener.co.nz/current-affairs/climate-change-current-affairs/how-to-make-new-zealand-low-carbon/

      Maclaren, Piers. ‘Environmental Effects of Planted Forests in New Zealand: The Implications of Continued Afforestation of Pasture.’ FRI Bulletin, no. 198 (1996).

      Hock, Barbara, Tim Payn, Peter Clinton, and James Turner. ‘Towards Green Markets for New Zealand Plantations’. New Zealand Journal of Forestry 54, no. 1 (2009): 9–20.

      Yao, R. T., L. E. Barry, S. J. Wakelin, D. R. Harrison, L. A. Magnard, and T. W. Payn. ‘Planted Forests’. In Ecosystem Services in New Zealand: Conditions and Trends, edited by John Dymond, 62–78. Lincoln, New Zealand: Manaaki Whenua Press, 2013.

  • Kia Ora David

    I am very impressed with your ethos behind your research and the pathway you have chosen to best utilise your expertise. This is in line with my own values with ensuring that everyone and industry can gain from sustainable investment, options and practice as an educational tool forward for all nations peoples and our planet. Starting with small steps such as yours (not demeaning your work at all, more in context to the current global situation), I vision a rapidly growing green system of carbon credit advantages and money in many more pockets.

    • Thanks for your thoughts Jewel – and you’re quite right, these are only small steps in a massive project, as well as only one dimension in what needs to be a multi-dimensional response to climate change. All best, David.

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