Are pine trees the problem or the solution?

Pine-forest regulation proposals are creating lots of heat with big implications for land-use and the landscape. 

Right now, there is a fervent debate underway as to where pine trees fit within our future landscape. On one side stand Forestry Minister Stuart Nash and Climate Change Minister James Shaw. They are proposing that existing legislation should be reversed so that pine trees would only be for production forestry and not so-called permanent forests.

Minister Nash has recently come to a position that only native forests should be permanent, and he is supported by many who hold strong environmental values. Dame Anne Salmond is one of the leaders in that camp.

In contrast, Minister Shaw is concerned that if permanent pine forests are allowed, then too much carbon will be stored in this way and urban people will no longer be forced to modify their carbon emitting behaviours. There are some huge ironies there.

On the other side stand iwi groups who own large areas of steep erodible land, often far from ports, for which permanent pine forests linked to carbon farming are by far the best income earning opportunities. These forests are also an excellent solution to the erosion problems.

Alongside these iwi groups, but perhaps not generally as well organised, are many pakeha sheep and beef farmers who also own areas of steep erodible land. If either economics or minimising soil erosion is the goal, then permanent non-harvested pine forests on this class of land are the obvious answer. Somewhat ironically, their industry organisation Beef+Lamb does not seem to support them.

Steeply eroding lands in the Wairoa district, April 2022

This overview might seem to describe a complex situation. Dig a little deeper and everything gets even more complex and confusing. Who is right and who is wrong?

As always in this world that we now live in, there is both information and misinformation. And some of the fervent believers do not understand when they are on shaky ground.

Both native and exotic forestry lie right at the limit of my former professional knowledge, which focuses primarily on agrifood systems. So, learning about forest ecology has been a journey of discovery. But having an education in agricultural science has meant that I do have some prior knowledge about the disciplines of soils, botany, chemistry and physics that underpin forestry.  Having studied economics through to post-graduate level also helps.

As for broader ecology, that too lies at the limits of my knowledge, although I did study some ecology a very long time ago. I also had opportunities a long time ago to learn some more ecology in the field as a Board Member for several years of Westland National Park. I have also been lucky to spend multiple years wandering and working in mountain areas across the world, observing nature in its many forms. All of this has been helpful in trying to put together the forestry jigsaw.

Here I want to focus on some fundamentals of introduced versus native forests, and perhaps dispel some myths as I do so.

The starting point lies many millions of years ago when New Zealand broke away from Gondwanaland to go its own way. For a long time, it went close to sinking into the ocean, but did manage to keep afloat as a subtropical outpost with vegetation that aligned to that environment.

Then more recently New Zealand became a land uplifted high by tectonic forces, with the vegetation evolving with that change. But plants evolve only slowly. Hence, we have no native pines nor do we have eucalypts. Rather, our dominant forest natives are podocarps and various species of beech (Nothofagus sp.).

Accordingly, in contrast to the Northern Hemisphere, our range of forest species is constrained in terms of resilience to diverse conditions. In the Northern Hemisphere, tree species have been able to march north and south across the land as the climate changed over millions of years. In contrast, New Zealand’s biota is restricted to what could first survive on a low-lying island outpost and then survive and evolve on a land uplifted high.

Outside of New Zealand, forests evolved in environments where there were many mammalian pests. In contrast, New Zealand’s native forests have been exposed to mammal pests only within the last 1000 years, and primarily within the last 200 years.

To cut to the chase, New Zealand’s native forest trees are not well suited to colonising steep eroded lands that lost their original forest cover between 100 and 1000 years ago and are now covered in rundown pasture and sometimes scrub, and which provide a home for introduced rodents and possums. Newly planted native forests need lots of tender loving care if they are to survive, combined with deep pockets of money to make it happen.  Even then, they establish and grow very slowly, with lots of failures.

My forester and ecologist friends tell me that outside of natural regeneration, we would be lucky in the last 100 years to have established 5000 hectares of native forest across all of New Zealand.  Where natural regeneration has occurred, it has been a slow process, defined by surviving seed banks, and often going through scrub phases before genuine forest species take over.

Fortunately, there are indeed many hundred thousand hectares of regenerating native forests, in contrast to the paucity of planted hectares. These are largely long-abandoned back-country farmlands with legacy native seeds, where nature has been left to do its own thing for much of the last 100 years . But if the criterion is carbon sequestration, or even protection of steep eroding land, then none of those regenerating hectares have been getting there quickly.  Even where seed banks are available, sequestration would be less than one quarter of what occurs in introduced forests. And none of those regenerating hectares are anywhere near back to ‘old man’ forest.

100-year old pines with native understory, near Kaingaroa Forest Village, sequestering >2000 tonnes carbon per hectare. Photo: Jeff Tombleson

Currently, in New Zealand we have approximately one million hectares, or perhaps a little more, of pastoral land that is seriously eroding. That makes up about 10 percent of the total pastoral land in New Zealand.  Putting a focus specifically on North Island sheep and beef land, then it might get closer to 20 percent.

Quite simply, if we want to protect that land and do it without sending the country broke, then pine forests of one type or another are the only way to do it.

If we planted out one million hectares of steep eroding land that has low farming value, then it would sequester well over 20 million tonnes of carbon per annum for the next 80 years and would still be growing strong at that time.  At current costs, it would cost about $3 billion to plant, but it would then return, once again at current prices, a carbon value of more than $1.5 billion per year.

Note also that the price of carbon is expected to rise, with the Climate Change Commission suggesting a price of about $140 is needed by 2030, and then heading on from there to $250 per tonne. So, why would we not do it?

The answer coming back from the ‘anti-lobby’ is that pine forests are ‘bad’.   But are they really so bad if properly managed?

One of the myths is that pines are short-lived species. Well, we have only had them in New Zealand for about 160 years but trees planted at that time are still going strong. The natural life of radiata pines is about 300 years and for redwood it is even longer.

Radiata pine tree planted 1868, Botanic Gardens Wellington. Photo: Graham West

Another issue is fire risk. Yes, that is correct, but non-contiguous plantings are one solution and there are other management strategies.

Actually, native forests also burn. That is how Maori first started the process of deforesting so much of New Zealand, continued by European settlers.

What about windfall?  Yes, that too can be an issue. The correct planting rate is a key part of the solution, and some places like the shallow-soil Canterbury plains are not the right place. However, some windfall is a natural process and part of the way that forests regenerate.

There are indeed some horrendous examples of what can happen when storms descend on pine-forest land that has recently been clear-felled, but that is not what happens in permanent forests.

What about wildings? Yes, in some areas that too can be an issue. However, radiata often gets the blame when the real culprits are the lodgepole Pinus contorta and Douglas fir.

I often say in relation to complex environmental issues, that if people think there are simple solutions, then that is because they don’t understand the problem. However, one thing that is clear to me is that among my network of experienced foresters, who do understand both native and introduced species, there is universal acknowledgement that permanent non-harvested pine forests are indeed a key part of the solution.

This is very different than what the key Government Ministers are currently saying. That raises questions as to who they are listening to for their advice.


This article is also published with an informative thread of over 100 comments at:

Earlier posts on these and related land-use issues are archived at

About Keith Woodford

Keith Woodford is an independent consultant, based in New Zealand, who works internationally on agri-food systems and rural development projects. He holds honorary positions as Professor of Agri-Food Systems at Lincoln University, New Zealand, and as Senior Research Fellow at the Contemporary China Research Centre at Victoria University, Wellington.
This entry was posted in carbon farming, forestry, greenhouse gases, Uncategorized. Bookmark the permalink.

23 Responses to Are pine trees the problem or the solution?

  1. Dr Mike Joy says:

    Keith one important factor is that neither pine nor native mitigate fossil carbon. The fossil carbon causing our climate problem today came from fossilised biology formed through ancient carbon cycles, mostly over the 200 million years of the Mesozoic era (ending 66 million years ago). If we put all the trees back we would mitigate the carbon loss from trees chopped down in the current carbon cycle but not > 66 million years ago, its just another way we kid ourselves.

    • jefftombleson says:

      Mike, all CO2_e is created equal whether its emitted from fossil fuels, an animal, or the local landfill ie CO2_e is based on its so-called global warming potential (GWP). The GWP of a gas is the warming caused over a 100-year period by the emission of one tonne of the gas relative to the warming caused over the same period by the emission of one tonne of CO2.

      The average amount of CO2_e emissions that flows through the atmospheric carbon cycle each year is estimated to be 200 billion tonnes

      55 billion tonnes of CO2_e annually is estimated to be human-caused GHG emissions.

      1.8 billion tonnes of CO2_e was based on global wildfires last year

      By 2030, 197 countries are required to halve their current GHG net emissions if warming is to level off at 2 degrees

      To achieve this target, 1 tonne of CO2_e emitted (irrespective of the GHG source or the year it may have been fossilised is equal to 1 tonne of CO2_e sequestered.

      Because of successive Govt inaction to implement policies to cut emissions eg ban the import of light vehicle combustion engines by 2030, NZ will be heavily reliant on sequestering CO2 from the atmosphere to meet its 50% reduction of emissions by 2030 and based on current technology will be reliant on the same in 2050.

      And the global target of achieving net-negative GHG emissions in the second half of this century with current technology will be highly reliant on nature based solutions ie new forests. And along with the thousand year journey to scrub every tonne of CO2 emitted into the atmosphere over the past 70 years, forest sinks will be the primary mechanism to assist the oceans to cooling the planet and hopefully restoring the climate.

      Globally nature holds no prejudice as to what tree species removes CO2 from the atmosphere. And the achievable challenge of reducing global annual emissions from 55 billion to 27 billion tonnes of CO2_e will be achieved with the combination of cutting emissions at source and CO2 Removals via expansion of forest sinks irrespective of the age of the CO2 atoms sequestered.

    • Pail says:

      Good point. There is only one way out, and it isn’t ‘net zero’, particularly if that just delays hard reductions of fossil burning releasing CO2, CH4 & H2.

  2. Isn’t one of the key things limiting pine forestation to the 10 per cent of marginal land that is eroding and that will never produce reasonable value on any normal, current farming practice? One scare story we had was that pine forestation would put a lot of farming applications out of business because of the carbon farming returns. If instead carbon farming was restricted to the identified marginal land, then that would have to be a net positive for everybody – farmers, carbon farmers, climate commission, and uncle tom Cobbley and all? I have seen rural lobby groups opposing carbon farming because it would remove farming practices that support current and future rural communities at scale. But if we are just tackling the marginal land then actually you make currently marginally-viable farming units that much more productive and viable, and so actually it would be a net positive for the rural communities that are otherwise rightly concerned about depopulation?

    • Guy Salmon says:

      Peter, I think there’s a bigger picture here. If livestock farming is going to have a long-term future in an emissions-constrained world, farmers will need opportunities to send certified, carbon-positive food to export markets. This strategy is being pioneered by Silver Fern Farms right now. For this to strategy to continue to work, farmers need to retain the opportunity to choose a mix of native and exotic species to get their farm to net zero. That ability to exercise rangatiratanga also pretty important if you think Te Tiriti ought to be part of our focus in this policy area. Kind regards.

      • Paul says:

        Pastoral food isn’t about ‘carbon positive’ , neutral or alike.
        We need to be talking about ‘climate neutral’ based on warming impacts as per Paris.
        Sure we could have a few farms ‘Carbon positive’, or some meat or milk ‘carbon zero’ (as per SFF & Fonterra). That’s just market talk. It isn’t a scale play

      • I totally agree. There are “win-win” solutions begging to be worked out. I have always thought that there are “branding” opportunities for NZ Inc in the primary sector that are just waiting to be used. And I don’t mean “green washing”. I mean real opportunities for changing the narrative in NZ and internationally for our primary sector so that climate change is actually seen not as a threat but as an opportunity for re-positioning in a much more savvy international marketplace that will add value to our primary sector while at the same time reducing its carbon and ecological footprint.

        Unfortunately, we are dealing with visceral rather than cerebral responses, the kind that had the Japanese and Norwegians promoting the killing of whales long after there was any rational basis for it because of a male stakeholder group that feared the alternatives, the kind of groups that saw the destruction of the cod fishery in Newfoundland. Almost the worst offender is Fonterra because it is such a big player and it is showing zero leadership as it finds itself down a cul-de-sac of maximising farmgate milk prices and a commodity volume model that could be turned around with NZ Inc branding, better marketing, and a commitment to added value while at the same time reducing the punishment meted out on the ecosystem.

        The current government completely missed a trick in the revisiting of the Fonterra Creation Act by failing to insist on added value and reduced ecosystem punishment.

      • Leveson Gower says:

        Hello Guy , this is an interesting subject . I agree we as farmers need to be able to use a mix of native and exotic plantings to future proof our farming businesses. The real issue here is that successive Governments have devalued indigenous bio-diversity on private land . In 1993 when the Forest Amendment act was introduced, we were told that our remaining forests would be entitled to pre 1990 carbon credits . This never eventuated and while pre 1990 owners of Exotic forests where issued with NZ carbon units , the units that should have gone to Native Forest owners where actually keep by the Government for their own accounting purposes. For the last thirty years as a country we have gone down the path of a rules based penalty system, to try and halt the decline in bio -diversity on private land . Private landowners who felled their forests in the 1970’s using Government incentives are now entitled to replant these areas and gain lucrative carbon credits while the owners who saw value in keeping their forests are still being harassed by more rules and costs . Private land owners need to be empowered to protect their Indigenous Vegetation , and this can be done by allowing them to claim the carbon sequestration of the regrowth that is in the understory of healthy mature native forests . It isn’t enough to say there is provision for this in the recent HWEN process . That provision is nothing more than a token green washing gesture . Deer numbers are about to explode , and this is going to put serious pressure on our bio -diversity. Governments and Councils cannot make enough rules and take enough rates to solve this problem. It can only be done by empowering the people with some real skin in the game to do the right thing by the environment and the Country for everyone’s benefit .

      • Keith Woodford says:

        You might be confusing me with Guy Trafford who also writes at

  3. Paul callister says:

    I have been involved in native plantings for the last 50 years – not at great scale but through restoration projects. But I have seem more recent attempts to establish natives at scale through ‘forestry’ style planting. I dont see it as realistic to plant vast areas of New Zealand in natives. It is too hard and too costly. I have certainly seen great examples of marginal land that has nearby seed sources of tauhinu, manuka and kanuka revert. And patches of bush on farms when fenced and pest control is good bounce back really well. I would love to see more native forest, large kahikatea and totara forests would be great to have. But native planting on bare farm land is not going to be the answer to sucking up carbon. We need exotics as part of the mix. But ultimately we need to drastically reduce emissions.

  4. granthod says:

    Great article and discussion, would be great to see this important topic broadcast at this depth on Country Calendar or Q & A

  5. granthod says:

    Keith, thanks very much for your lovely eulogy for Rod Thomson, sorely missed friend

    Ngā mihi

    Grant Hodgson

    Mobile: 021 439 704

    Sent from my iPad


  6. Keith Woodford says:

    Thanks Grant,
    I think Rod’s death came as a great shock to all of his friends.
    I am still struggling to come to terms with it.

    • granthod says:

      Me too. My wife went to school with Sarah, and our families spent a lot of time together, September lambing and Christmas down at the river, our kids basically grew up together. Hard to make any sense of it, really, and very sad.

      Ngā mihi

      Grant Hodgson

      Mobile: 021 439 704

      Sent from my iPad


  7. Paul says:

    That picture saying ‘>2,000 of Carbon per hectare’.
    It seems a lot based on the density of the trees in the picture. That would be >7,000t of CO2/ha.
    To suggest doing such on ‘highly erodible’ steep land like skeletal soils would be a disaster long term. Such LUC areas would have likely held ~200-300t of carbon per hectare in natural form.
    So to your point, such a simple exotic pine permanent forest on such steep hill country is anything but.

    • Keith Woodford says:

      When people talk about ‘carbon’ in a forest then that is always shorthand for CO2.
      I took the figure from Jeff Tombleson but I think he is a reliable source on these matters.
      When the forest is mature, I would expect that there would be stable biomass. Individual trees die at different times and are replaced by new trees. Similarly, root carbon will also reach stability. As old trees die their carbon is released to the atmosphere and new carbon is sequestered from the atmosphere by the new trees, thereby retaining the balance.

  8. waimata says:

    I see the major issue with carbon forests is the reality that these forest will become senscent one day. There needs to be some mechanism planned in adviace to handle the huge amount of biomass that will eventually be collapsing into these new forest ecologies, even if it is 150+ years in the future.
    There are other exotic tree species capable of good growth rates close to pine, with far more valuable timber in which some kind of continuous cover forestry is not infeasible. We just need a high value market.

  9. Greg says:

    I’m glad to see that one of the first comments on Interest was about northern-hemisphere temperate climate broadleaf forest (oak, in the comments).

    If we are serious about sequestering large amounts of carbon for the long term, then we must reject any binary choice between P. Radiata and natives, neither of which do a good job. There are alternatives. Yes, they require more knowledge and more thinking.

    Our ecopoiesis (:”artificial creation of sustainable ecosystems”) needs to take a longer and wider view.

  10. jefftombleson says:

    Paul, yes, the 100-year-old radiata pine stand is impressive. 100-years of removal from the atmosphere and store of 2,000 tonnes of CO2_e per hectare is certainly a credit to the taonga of radiata pine. This plantation was established at approximately 2,300 seedlings per hectare (6 x 8 feet) and with no management intervention has naturally thinned to just 84 trees per hectare. The plantation has been subject to numerous storms including cyclone bola and has remained stable and may remain so through to its life expectancy of around 300 years.

    Unfortunately it is located more than a bird flight distance from the neighboring Tarawera native forest or the Whirinaki Conservation Park that would have enabled the natural introduction of tall timber native species that would thrive to eventually replace the store of atmospheric CO2 albeit at a lower level. The cathedral stands of Aotearoa’s native conifers in the neighboring Whirinaki Conservation Park aged around 600 years are likely to be storing well over 1,000 tonnes of CO2 per hectare, and just like radiata pine, such stands in the event of major storms are subject to windfall that ensures forest sustainability.

    Aotearoa’s current climate emergency focus is on halving its net emissions from around 80 million to around 40 million tonnes annually by 2030. Such a reduction is to be achieved by cutting emissions at source and removing atmospheric emissions by expanding the existing 700,000 hectare forest carbon store established since 1989. Minister Shaw advised during COP26 that 70% of NZs 2030 emissions reduction target will come from an Asia Pacific mega afforestation project that is estimated to cost between $8 billion and $12 billion.

    Farmers hold the key to meeting NZs emissions reduction targets not only in 2030, or 2050, or the second half of this century to achieve net-negative GHG emissions but for the thousand years to come to assist the oceans scrub every tonne of emissions from the atmosphere that NZ has emitted for the past 70 or more years that will cool the earth and hopefully restore the climate

    The establishment of 1.3 million hectares of radiata pine nurse crops by farmers over a 13-year program on higher rainfall and the most non-food producing status land possible within a birds flight of native forest would achieve outstanding results and in combination with cutting emissions at source could not only achieve the required 2030 emissions reduction target but achieve net-carbon zero 2040, and it all happens on our shores

    To make this happen, participating farmers should be handsomely rewarded via the Govts quarterly auctions of virtual carbon credits that is raising over $2 billion annually and doubling to over $4 billion by 2030.

    It’s time we had climate change mitigation, evidenced based leadership not by well meaning officials but including farmers who hold the key for not only the immediate and critical eight year journey to 2030 but the thousand year journey ahead. (and these posts by Keith Woodford are facilitating a sterling effort to steering such evidence based leadership)

  11. Great points by Peter Davis and Jeff Tombleson! We should be looking for win-win solutions. Carbon forestry does not need to happen at the expense of natural regeneration – quite the opposite – one can fund the other! And if we embrace continuous cover forestry and selective harvesting methods then it does not need to result in unproductive land either – timber is a fantastic renewable resource that is likely to replace concrete and steel and other carbon-heavy materials in the coming decades.

    Carbon Critical has put together a little web dashboard to help people understand the general trade-offs for different afforestation strategies:

    We would like to see the government take a pragmatic and evidence-based approach to achieve the best possible outcomes with the tools we have available. There are really big opportunities if we can be more imaginative with how our carbon markets work. For example:

    * The government could tax carbon transactions so that different prices apply for emitters and suppliers. For example, emitters could pay $140/t, and foresters could be paid $70/t, with the difference going into the public purse. This could provide massive subsidies for climate mitigation and adaptation, conservation projects, predator/pest management, clean infrastructure upgrades, … not to mention proper and rigorous management of permanent forests (native and exotic).

    * We could also plan to sell any surplus credits we have on the international carbon market (instead planning to spend billions of dollars on foreign offsets). Global demand for carbon removals is absolutely phenomenal – the UN IPCC says to avoid worst case climate outcomes the world will need to be able to drawdown 10 billion tonnes of CO2 per year, every year, from the year 2050 onwards. (Current global emissions are about 55 billion tonnes). As far as NZ is concerned: unlimited demand

    * With unlimited export demands, the government could also lock-in unit prices: the Climate Change Commission has said prices need to reach $140/t by 2030, and $250/t by 2050, for the ETS to act as an effective deterrent to emitters. So let’s commit to that trajectory, and stop acting like the ETS is a beast beyond our control

    If we decouple supply and demand via taxes and international markets then the government can control domestic supply and pricing without impeding the unique opportunity we have in NZ to remove vast amounts of carbon dioxide from the air. It just needs strong vision and leadership and careful planning and management.

  12. I would like to add into your thoughts, the idea of diverse land use, why must we just populate with one species and only see soil erosion as the focal point to savings our ecology and economy.

    • Keith Woodford says:

      Hi Bonny,
      There is a range of land classes in New Zealand. For privately owned land on steep eroding country, then introduced species of trees, but not only pine, are the options that ticks the boxes of erosion, sequestration, practicality and economics. The science (as opposed to the commonly held perspective) is that this also ticks a box for biodiversity, with this being much greater than with the only other practical land-use which is pasture.
      Appropriate and practical land uses are different for each class of country.

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