How I grew, and lost, a rainforest

And so I’ve come to the end of my posts concerning Part II of A Small Farm Future and I shall soon be moving onto Parts III and IV, which are the ones that have generated most of the discussions and disputations over the book. I include this post by way of a deep breath, reflecting back on the ground we’ve recently covered and forward toward what’s to come.

Let me begin by reprising the tale of our woodland here at Vallis Veg, which I’ve previously discussed here, among other places. Between 2004 and 2007 we planted seven acres of young saplings on our site, which have now grown into some pretty hefty trees providing numerous benefits – constructional timber, firewood, food, wildlife habitat, wind protection and recreation among them. I’ve discussed before the debate about whether it’s better to allow natural regeneration, or to force the issue by planting saplings, as we did. In any given situation there can be arguments either way, with the balance of them perhaps usually favouring the low input natural regeneration route.

But I’ve come to think of this debate as rather pointless. Given the human dominance of the farmed landscape, what really matters is the decision to opt for trees. If you take the natural regeneration route, you’ll probably lose several years of potential tree growth – which could be significant for humans on our short-run timescales, but not really significant on forest time. In our woodland, wild trees and herbaceous understory plants that we never designed into the system ourselves are beginning to make their presence felt. In a few decades, I don’t think it will have mattered much to anybody but ourselves during a few head-start years how the trees came about. Aside from the possibility that climate change will get the final word, soon enough the only thing that will matter is whether the people who are stewarding the land after us suffer the woodland to continue or not.

Campaigning eco-journalist George Monbiot makes a good case for reconsidering parts of Britain’s woodland cover as rainforest, a resonant word that might make us re-evaluate the way we think about our trees. He defines rainforest as forest wet enough to support epiphytes such as mosses. In the same article, he goes on to make a slightly less good case for preferring natural regeneration over tree-planting on various grounds, including the notion that a plantation “takes decades to begin to resemble a natural forest”.

So let me present to you Exhibit A – a tree we planted that’s now encircled with epiphytic moss. And Exhibit B, a view of part of our woodland shot from behind Vallis palace that I’d suggest arguably does at least ‘resemble’ a natural forest. Reader, I grew a rainforest in fifteen years!

I don’t want to go out of my way to annoy George, but I can’t resist also presenting Exhibit C – ovine silvo-pasture. But, talking of livestock, let’s go back to Exhibit A. What is that unsightly gouging in the soil around my moss-encircled rainforest tree? That, my friend, is the work of two pigs I’m currently raising. Which perhaps is problematic, at least if you follow the advice of my fellow Chelsea Green author Steve Gabriel in his interesting book Silvopasture. Steve argues that the rooting of pigs too easily disturbs the soil around trees, threatening the long-term survival of the trees to the extent that pigs are not a great choice for agroforestry livestock, despite their woodland origins.

It’s not my intention to pick a quarrel with Steve, who I’m sure knows a great deal more than I do about agroforestry systems. In the case of my own particular system, I usually raise two pigs over six months out of every two years in about two acres of mixed woodland, grassland and cropland with supplemental feeding, which I think keeps the habitat pressure relatively low. Even so, it’s possible that the depredations of the pigs seen in Exhibit A will prove lethal in the medium term to that tree (the pigs seem to home in on particular trees and grassland patches, leaving others undisturbed). So perhaps I will be guilty of destroying a rainforest not long after growing it, though the likely death of its ash trees seems a weightier matter, and one that’s beyond my control.

But I can’t summon an awful lot of anxiety about the pig damage. People have learned a lot in recent times about the intricate complexities of old growth forests and the extraordinary symbioses between their plants, fungi, animals and microbes. But I fear this too easily generates a misplaced snootiness about younger growth woodlands and the simpler, more aggressive interactions they contain, where trees have the role of what forester Peter Wohlleben calls ‘street kids’, prematurely left to fend for themselves in a risky, live fast die young lifestyle.

Wohlleben himself shows in his book The Hidden Life of Trees that even in the absence of human intervention the road to old age for a tree is strewn with dangers, with most never making it. And why in any case should the absence of human intervention be a relevant datum? Humans, like pigs, play the ecological role of patch-disturber, holding up ecological succession and introducing greater mosaic diversity into the landscape. This is not in itself an ignoble role, even if the number of people and the number of pigs in the world today has made us more than ‘patch’ disturbers. Organisms that cause trees to grow or not to grow and cause them to fall before their time are another part of woodland ecology.

Simon Fairlie wrote a fascinating chapter in his wonderful book Meat about the trade-offs between grassland and woodland in agriculture that he called ‘The struggle between light and shade’. This speaks to an open question in our farming systems that we can never quite get right – how much patch disturbance and how much succession, how much labour input and how much nature’s way, how many perennials and how many annuals, how much grass, how much woodland, how much cropland? As my pigs root among the trees, I’m conscious that this question is forever open – and I’m only one of the protagonists in it, who doesn’t necessarily get the final word.

But as I turn my attention in forthcoming posts to the more political and social aspects of farm systems, I want to interpret the ‘struggle between light and shade’ more metaphorically. So much of our thinking invests itself in totalizing dualities. Right versus wrong, good versus evil, truth versus error, ‘science’ versus ideology, righteousness versus sin, or light versus shade. As I prepare to wade into the partial and messy world of human affairs and opinions, in which I hold some pretty firm ones of my own, I want to pause for a moment in the forest’s dappled glades that the pigs have opened up. Neither right nor wrong, neither light nor shade. This is not a vapid argument that the ‘middle ground’ is always best. Perhaps it’s just an argument for a bit of intellectual patch disturbance, to follow the pig’s way, without pre-commitment to the benefits of either light or shade.

31 thoughts on “How I grew, and lost, a rainforest

  1. Copicing ? Thousand of acres of England were put down to copice , as plastic gets more expensive ( here in TX the price has doubled this year for plastic beads to manufacture into product ) a few years and you could start making baskets as another sideline .
    I have walked coppiced woods there is a myriad of understory plants that grow.
    Pigs will kill trees hundreds of acres of trees are destroyed annually by feral hogs here in TX , the understory is chewed up ,any bulbous roots are eaten , ( think small bulldozer damage )

  2. Intellectual patch disturbance…

    If only Monty Python were still writing (I see the big foot squashing something).
    Constitutional peasants and all that rot. Nicely done.

    Still, a few questions:

    Is the trail of disturbance left by the porcine members of the farm actually damage?

    In the realm of a wood, can you – current landholder that you be – actually be assumed a protagonist? [see the treatment of King Arthur in constitutional peasants for a spin on that line of thinking]

    And perhaps this is an English thing – but is truth a suitable opposite for error?

    I am most grateful for this post. Lots to chew on. If words were calories I’d be gaining weight right now.

  3. In Sweden the number of boars are booming, well over 300,000 and I can assure you that the soil in our fairly old growth forest is disturbed by them, but seeing that as damage is a rather limited perspective. Biodiversity benefits from a certain level of disturbance rather than climax vegetation. Having said that, I have also seen a number of patches of domestic pigs really destroying most of the vegetation. I guess it can be discussed as a kind of overrooting…..I tend to agree that is is unecessary to have a very strict line between a plantation and natural regeneration, I think we need to consider the context and how plantations are made. My inclination is skepticism of plantations because O I have seen sooooo many bad examples in most continents, especially when it takes place in “projects” or on agriculture land. In Sweden there are some 500,000 hectares of former ag land that has been planted with spruce in straight lines. I would say these forests are dreadful from all perspectives, including from a forestry perspective. With plantations in forest land, even if you plant spruce and pine you will get lots of birch trees, aspen, alder and others depending on the local conditions. I consider it a waste of time and energy to actually plant trees in forests and it applies mostly to when you clear cut, which is another discussion. But again, I do believe that people can make wonderful forests by planting trees..
    A little side note: the EU plans to plant 3 billion trees in ten years. It made me smile as Sweden alone plants 400 million trees every year……

    • The US plants about 1.6 billion trees a year, albeit mostly in plantations by forestry companies.

      I once lived surrounded by Douglas Fir plantations that were established after the old-growth fir had been clearcut in the early part of the 20th century. Once those second-growth forests became old enough (80-100 years), they were very productive ecosystems with a great deal of similarity to old growth forests.

      Here in Hawaii we have some planted forests that were created as CCC projects during the Great Depression. The trees are about 80 years old now and the forests are impressive. Give any group of trees enough time and they will create a productive ecosystem, no matter how they got their start.

      Indigenous people all over the world affected the forests they lived in. Here is an interesting article about how Native Americans used fire to affect their surroundings, often dramatically. The rapid depopulation of the Americas after European contact obscured the scale of the deliberate management of forests there, leading European ‘explorers’ to wrongly view much of the landscape as pristine wilderness, when it was nothing of the kind.

      https://www.history.com/news/native-american-wildfires

      My takeaway is that outside boreal regions a forest wilderness is actually fairly rare and that the best way to interact with forests is for people to live in and around them for a few thousand years so that best practices can evolve ‘naturally’. Chris is just getting started. The Smaje Grove will eventually be the Wonder of Wessex.

      • Joe “Give any group of trees enough time and they will create a productive ecosystem, no matter how they got their start.” I certainly subscribe to that.

        Nature prevails and even if there are talks about the 6th mass extinction I am more concerned over the extinction of the human species than the extinction of healthy eco systems.

        In the boreal area “enough time” is a very looong time, though.

    • In Sweden the number of boars are booming, well over 300,000 and I can assure you that the soil in our fairly old growth forest is disturbed by them…

      Perhaps it is time for another Boar War. I think the British Army has some experience fighting Boars…

      Oh wait, did I misspell that?? Oops, my bad.

      Sorry, couldn’t resist – that the Boer’s were farmers, and that colonialism was expressed on both sides while indigenous folk were caught up in the struggle (and Jolly Ol England was knee deep in it) – how could I?

      Jumping ahead though I could see a peace treaty being held between a victorious Sergeant Major and a Chester White boar (or a Hampshire, no, no, a Gloucestershire Old Spot; nope? how about a Berkshire? Oxford Sandy and Black then?)

      And why might I assume the humans would be victorious? I’m wondering that myself. If there are over 300,000 in Sweden alone you might imagine they’re pretty good at this game already.

  4. Wild boar were rampant here until about two years ago when swine flu decimated the population to the point that you seldom see signs of their rooting around, and I haven’t seen tracks in the mud for months. It’s interesting to see how they can really go to work on a piece of land, but not always such a welcome sight in the farm or garden.
    Deer also seem down in numbers, but this varies anecdotally: the foresters (who you would think should know) say the deer have disappeared and point to the rising population of wolves; the hunters say they can still find deer to hunt; the wolf experts say there aren’t that many wolves to explain the seemingly sharp decline in deer. Bears are also up in numbers – a man was killed by one in Slovakia last week, first time in a hundred years in this part of the world.
    The often observable if inexplicable rise and fall of the numbers of other creatures is one of the most fascinating things about living and working within a green environment, among verdant hidden hills. It peppers the conversations, and calls one to look and look again at what is happening right now around you, which is often surprisingly easy to neglect when working on a piece of land… The donkey brays from up the field, bringing me back to my senses: he might need fresh water.

      • When it’s announced that there are targets to plant so many millions or billions of new trees, the numbers sound impressive but it would perhaps be more revealing to put it in terms of ‘increasing forest cover to x percent, from the current x percent’. X million trees might only mean a minuscule increase in tree cover for a given country. That’s not a criticism, just a suspicion that obfuscation can creep in when govts. make announcements along these lines.

        • Agree totally, in addition there are many places where afforestation makes little sense. England probably needs more forests and they will probably thrive there, but in many drier landscapes planting trees is a waste of energy, better to let i be grasslands, savannes, steppes etc.

          • Considering the brutally significant storms and hailstorms being experienced somewhere in Europe (as elsewhere) on an almost daily basis during this summer’s heat (not to mention the tornadoes!) I envisage that sacrificial trees/shrubbery might come to play an increasingly important role in shielding buildings from the worst of storms’ impact in order to protect windows, roof tiles, etc. Shrubbery that can withstand a tornado might be a gap in the market. Unfortunately, most buildings are starting to appear woefully inadequate for the ‘semi-freak’ weather at 1.1-1.2C above pre-industrial average temps, with more warming to come. Ah well, it’s one way to get closer to nature I suppose.

    • TX ” feral hogs ” are just difrent than wild boar though they are a cross between escaped domesticated pigs and wild boar imported by some nut that wanted some shooting around 1930 , there are between 3and 7 million. If them depending on whose estimates, they root and eat the surface roots of trees which kills them , they are dangerous , last year a nurse on a early call was killed and partially eaten in a housing development here in tx. They can get big 400 pounds is not uncommon and hitting one in a car usually means the demise of the pig and the car , I have seen them Knock the front axle out of a semi ( tractor unit , UK ) . Yes domestic pigs can and do clear brush in forests they are very good at it but left too long they will destroy the habitat .

  5. A hidden haiku by Chris Smaje, from the closing paragraph:

    forest’s dappled glades
    a bit of patch disturbance
    follow the pig’s way

  6. Thanks for all the interesting comments.

    Coppicing indeed is a noble art, which we practice in moderation here at Vallis Veg. Though more often pollarding, on account of the livestock and the deer. However, it doesn’t escape the issue of soil/root damage.

    Disturbance or damage, now there’s a question! And who gets to decide? Ultimately, it must surely be a matter of degree, of finding an equilibrium. Humans will experiment for their own purposes, and eventually figure out systems that may work for a while. Gaia will work on longer timescales, with logics we can only guess at – in fact, probably with no logics at all.

    I’m interested in the proliferation of boars in Sweden. Where does hunting fit into the picture? Also interested in natural ebbs and flows in Hungary. Is there a Yellowstone effect, where a small number of wolves have a disproportionate effect on deer numbers?

    On such matters, I certainly found that living for a while in bear country concentrated the mind. People spent a disproportionate amount of time discussing the dangers, relative to the small risk of an attack.

    As to Boers, hmm well, the imperialists in pursuit of the colonists – two iniquities that fail to cancel each other out. This touches on an issue I plan to raise in future posts, so I won’t bore you with it now. But I would recommend a look at Reviel Netz’s thought provoking book ‘Barbed Wire: An Ecology of Modernity’. First deployed in the USA to dominate cattle, then in South Africa to dominate colonists, then in Eastern Asia and Western Europe to dominate soldiers, then worldwide to dominate civilians.

    I agree with the points about tree/shrub cover and climate change. Perhaps successful climate change adaptation in many places is going to mean a lot of labour-intensive woody plants with annuals in ‘sparsely-distributed garden-sized patches’. In other words, A Small Farm Future (see p.113).

    It seems like we’re all mostly in agreement about the rights & wrongs of plantations vs woodland regeneration – thanks for the various interesting illustrations. Possibly more by luck than judgment, our little plantation has already more than offset the costs of undertaking it by all criteria that seem relevant to me, and the rest is out of my hands.

    I’m not feeling philosophical enough today to address the truth of the distinction between truth and error, so I’ll simply end on a more aesthetic note by appreciating Steve’s haiku.

    • Re: bears,
      I lived in ‘bear country’ for a few years in northern California, and I never gave a thought to bear attacks on my person except for that one time I stared one down with a flashlight as I was trying to make it leave my little orchard. And even then, I didn’t get more than two steps from the door of my house.

      But bear attacks on my apple trees! Those were serious. It is easy to keep deer out of an orchard, but I’m not aware of any (affordable) way to exclude bears.

      Nice haiku.

    • Re, the Yellowstone effect, thanks for bringing that up, Chris. I hadn’t previously read into it, but it brought to mind a talk I watched by Brazilian farmer Ernst Gotsch who explained how “hunger is the not the predator’s motive for eating, but the means for accomplishing its role of optimising the number of prey, in accordance to the capacity of sustainability of the ecosystem”, via an interesting story from his time working with indigenous shepherds in Namibia. From this principle he extrapolates a paradigm of unconditional love and cooperation that exists in nature. For anyone interested in the story – involving the fascinating interplay of weather and breeding patterns, predator and prey numbers, and deep indigenous knowledge – it’s at around 28 minutes into this lecture:
      https://www.youtube.com/watch?v=9zhTsYgfuyQ
      It could be that deer have also been forced into new territory by the sudden presence of a few wolves. The hunters that are having no trouble shooting them operate way over yonder. But I’m sure, come early September, we’ll hear lowing stags in the dark once again. You can almost set your watch by that.
      PS Your downpipe has come loose on the NE wing

  7. They shoot some 100 000 boars annually, but it doesn’t seem to be enough. The government has finally acknowledged the problem and is relaxing some regulations around sales of game. I got 2 boars (and a row deer and 1/4 of a moose calf) from “our” hunters last year – excellent meat. 2 kg of game per capita per year is provided to the Swedish market, more or less the Eat Lancet provision…

  8. Pingback: How I grew, and lost, a rainforest – Olduvai.ca

  9. The book quotes a study suggesting that in northern Europe, walnuts yield half as much food (presumably kcal/ha.y) as wheat. But I don’t think this is a fully like-for-like comparison.

    1. Walnut trees yield nuts year after year. Continuous wheat rapidly runs out of steam and needs to import fertility from elsewhere on the farm.

    2. Some people, admittedly perhaps after a poor diet in childhood & youth, have become very unhealthy, even diabetic in middle age and have only recovered by following a high fat, low carb diet. See e.g. the work of David Unwin, NHS GP and experience of Tom Watson ex-MP, also disturbing evidence from ancient Egypt on the lack of health of people. That suggests caution over a diet based on wheat as a staple food, although long fermentation may make bread non-toxic enough (except for the 1% of us who are coeliacs) to include in the diet of most people. I don’t know anyone who finds that they need to avoid walnuts in the diet.

    3. The walnut tree canopy may be 3-15 m above the ground. One can still do something on the ground … maybe graze ruminants to make cheese or butter (conversion of wild vegetation to dairy produce is apparently more energy-efficient than wild vegetation to meat … obviously dairying leads to some meat as a byproduct, just not much).

    4. The land on which one hypothetically grazes sheep to make a cheese like Manchego – Pecorino would be even better – and which rains walnuts once a year, may produce as much food – and rather healthier food – than even an organic wheatfield. Has anyone looked at the figures?

    5. The CO2 balance of trees on permanent pasture might be significantly negative, i.e. good. From what I’ve heard, cornfields on an organic farm, the usual rotations and cultivation to control the weeds may struggle to keep the farm CO2 balance zero, i.e. less good.

    6. A rather rhetorical question, I hope. Did the bison and other ruminants which grazed the prairies for many millennia lead to a severe buildup of methane in the atmosphere, leading to severe global warming? If so, maybe there’s a difference in soil life between temporary, i.e. cultivated, pasture and never-cultivated pasture.

    • I love the idea of nuts, but one member of my household is allergic to walnuts and I don’t get on well with hazelnuts (I love them, but every time I eat them I have skin problems; I’ll eat them anyway as a treat but making them a staple seems like a bad idea). Nut allergies are not uncommon.

      And there’s the whole issue of squirrels, discussed at length in a previous post…

      I think you’re right that it isn’t quite a like-for-like comparison, but I’m not sure how practical an alternative walnuts make to wheat.

        • Sorry to hear about the walnut allergy. Does anyone these days in ‘rich’ countries propose a single ‘staple food’? I don’t know how anyone would get all the essential nutrients … there’s too little potassium in animal-based foods, there are too few available EFAs in plants unless you’re very lucky on your internal enzymes, etc.

          As I said, based on skeletal examination, including people’s height, the ancient Egyptians seem to have had poor health on a varied diet which was rather rich in wheat.

          AFAIK the ‘Blue Zones’ featured a rather varied diet … they probably still do, if American junk food hasn’t totally taken over and ‘triumphed’. I read that it has in Okinawa, sadly.

          • David said:
            there are too few available EFAs in plants unless you’re very lucky on your internal enzymes, etc.

            Maybe I’ve been reading from the wrong sources… but the only two essential fatty acids for humans are linolenic and linoleic acids. And a couple of plants we’ve recently discussed here are exemplary sources of both: canola oil and soybean oil. In fact the fatty acid reference I have to hand actually ranks soy and canola far ahead of animal fats like lard and beef tallow in their relative percent of these two EFAs.

            Just because these fatty acids are available from plants doesn’t mean I want walk away from a diverse diet which includes animal sources of nutrition… just hoping to set the record straight.

          • More practically: there will always be people who can’t eat one thing or another. A strength of smaller, local systems is that if I need to grow more potatoes and less wheat, or more chestnuts and fewer walnuts, there is scope for that in a way that is simply not possible on, some larger industrial farms.

  10. Long time listener (well, kind of…okay, not really), first time caller here. Rather than approaching it from a neither/nor direction, why not a both/and direction? Rather than neither light not shade, both light and shade. Maybe that’s effectively the same thing, though the latter, to my ear at least, is more intriguing and inviting. To take the example of silvopasture, the both/and is kind of the point, is it not? Both trees and pasture. Both light and shade.

    As to the “how much” question, and the thought that “we can never quite get [it] right,” I am reminded of an ancient philosophy class I took in col!ege, about which I could tell you practically nothing (my brain has in the meantime become occupied by other things) except this: the professor was describing in pictures a process of thinking about certain issues. Looked at from above the process appears to be a circle, where we seem to keep coming back to the same place over and over again (that is, never quite getting it right). But looked at from the side you add another dimension, and realize that though in going round and round you appear to be arriving again in the same place, you are actually gaining in elevation (of a sort) with each trip around, so that the picture is not that of a circle, but more like a slinky. So though we keep going around, we are gaining knowledge and experience with each trip, and refining as we go (so still not quite getting it right, but at least getting it…righter?).

    And I’d probably posit that that’s actually a good thing. (For that matter I don’t think there’s even another option, so whether it’s good or bad is probably irrelevant.) It keeps us involved, keeps us invested.

    On the practical matter of pigs, I love the look of pigs out on grass and/or under a canopy of trees, and from time to time have used them to clear ground for one reason or another. But management can be a pain, and there are typically plenty of other ways I’d rather spend my time, so now I’m happy to keep them confined to a relatively small pen with deep bedding and feed them on clabbered slim milk, garden and kitchen waste, weeds, and some soaked purchased grain. I could run them through our woodlot to let them forage for acorns and roots and whatnot, providing a more natural habitat for them, but that would likely displace a certain number of our native whitetail deer and squirrels (among other critters, of course) that also utilize those foods, and that’d be a shame. So I keep the domestic animals out of the woods, and get to eat the domestic AND wild critters.

  11. I may have missed it in this excellent discussion, Chris. But what breed of hogs are you raising in the woods? That does seem to make a difference for us on our farm. We have found that the lop eared varieties like Gloucestershire Old Spots or Large Blacks do not disturb the ground as much. At the same time, because they can’t see (with their large ears over the eyes) they are not effective rooters and need more prepared feeds. When we use a Yorkshire, Tamworth, or Durocs, all bets are off on the woods. The damage even in the six months we keep them in rotating paddocks is immense. Yet, they are easier to grow out and require less additional feed.

  12. Hi, thanks for the further comments – especially from the new commenters – and apologies for the slow reply. More than usually busy ATM, alas.

    Thanks to David O for those points of interest. I’d say that walnuts are a bit marginal in our bioregion, but yes they & other nuts can be competitive as you head south. There are long-term wheat systems like John Letts’ that we discussed a while back, but with lower yields – so generally walnuts might be more benign ecologically, although are they not allelopathic? I’m not a massive fan of walnuts myself, though I do prefer the fresh ones we grow than commercial offerings – still not sure about nuts as a staple (a bit too strong tasting?) though I think David is probably right to be questioning the whole idea of staples. The nutritional rights & wrongs of different foods is a place I rarely go on this blog, but I think I’d be willing to trade off a little health over the years for bread over walnuts. Point 3 may be true, but also applies inversely to a wheatfield – one can do something in the air. I’m sceptical that pastured meat would add a great deal to the calorific/protein quantities on a per acre basis, but it could certainly work as part of a larger system. On carbon, yes I think a tree/pasture system would be better, if it produces enough on an acre for acre basis. And no, premodern ruminants were not a climate forcing problem (nor, arguably, are modern ones, as previously debated here…)

    To Wes’s points – yes I agree, both/and to light and shade. I also agree about the hidden progress sometimes involved in going around in circles, but I think a little humility about the imperfections of our agricultural simulacra is usually in order. I do still think that here in the far northerly latitudes present human numbers demand more light than the trees would be inclined to allow us, meaning that work is still needed to hold up ecological succession.

    To Brian’s question, this year I’m raising a commercial middle white breed because I couldn’t get more traditional breeds. I’ve raised Old Spots and Tamworths previously – I’ve noticed more docility in the former, but not necessarily less rooting or damage. Perhaps I need to observe more closely…

    Thanks also for the other comments!

    • Some wee remarks, after spending inordinate amounts of time looking into land carbon sinks recently in the course of my work:

      It is not the woodland that is the carbon sink. It is the transition from grassland to woodland. The carbon stock per hectare increases from a lower equilibrium to a higher equilibrium over a century or so. When the higher equilibrium is reached it stops increasing and the woodland ceases to be a carbon sink.

      Same with holistic grazing. If you take degraded land (old arable land for example) and restore it, then it will be storing carbon year-on-year until it reaches a higher equilibrium. If you implement holistic grazing on land that is already high in soil carbon, then there is very little if any possible gain.

      Consequently, the best thing (in carbon terms, and aside from the obvious solution of leaving it deep underground in the first place) we could be doing is converting the lowest-carbon soils to woodland.

      There are obviously big caveats. In places where forests are not the climax vegetation, the above doesn’t apply in the same way.

      On “premodern ruminants were not a climate forcing problem”, a brief treatment of the subject can be found on p. 80 of the ‘Grazed and Confused’ report: https://www.oxfordmartin.ox.ac.uk/downloads/reports/fcrn_gnc_report.pdf. I’m not sure whether the conclusions of the report appeal to this blog’s author and readership, but within the limitations of a “we must feed the world” paradigm, I found it relatively balanced with the occasional ideologically-based statement thrown it. The short bit on prehistoric ruminants is quite good.

      On planting trees versus natural regeneration, the latter has a significant advantage in carbon terms. Planting trees, even when done “by hand”, disturbs the soil and releases carbon. This, combined with the time it takes for tree seedlings to get established, means that planting trees can actually be a net source of carbon emissions for the first 10 years or so. Given the timescales we have left (about a decade or two) to tackle climate change, tree-planting is arguably irrelevant and possibly counter-productive on that basis. Natural regeneration doesn’t suffer from the soil disturbance emissions, but it is slower, and you’re left with a species mix determined by the local seedbank (which, if you’re unlucky, could have no tree seeds at all).

      Obviously, given most scenarios for 1.5 degrees C require large amounts of negative emissions in the latter half of the century, and expanding woodland cover is the only existing means of pulling carbon down from the atmosphere, planting new woodlands is probably still a good idea.

      • Thanks for that Joshua. My remarks in the post itself were not addressed to carbon/climate change at all. Of course, it’s an interesting dimension – but as I think you’re hinting yourself, the issue of woodland or grassland management as climate change mitigation seems to me largely a red herring.

        Regarding the carbon cost of tree planting, no argument from me there – although I doubt that the soil disturbance of hand-planted saplings is the main component. All the same, one presumably has to put it into a lifecycle or opportunity cost framework. During the time lag of natural regeneration, what alternative methods might we have used for wind protection, space/water heating, fodder, privacy to facilitate onsite living etc. and what carbon burdens might they have involved?

        Regarding methane, wild ruminants and the Grazed & Confused report, my suggestion that the methane emitted by prehistoric wild ruminants was not climate forcing is not inconsistent with the report’s suggestion that temperatures may have declined with the decline of wild ruminants. It seems to me likely that major declines in wild ruminants prehistorically or farmed ruminants today ‘may have’ a short-run depressing effect on temperature, in the rather uncertain phrasing of the report. But IMO this carries no implication that reducing farmed ruminants today should be a policy priority remotely equivalent to reducing fossil fuel combustion.

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