Trees Are Not A Renewable Resource
If you thought trees are a renewable resource, something we can use to substitute our fossil fuel obsession, think again.
Why is everyone talking about trees?
As you research climate change mitigation, you find solutions that involve trees. Over and over again, journalists, environmentalists and scientists discover ways in which trees can replace fossil fuels, either by sequestering carbon or replacing plastics or replacing concrete or replacing coal. All of these ideas assume trees are a renewable resource and carbon negative to boot.
But are they? And are there enough of them to solve our problems? Let’s find out.
We’ve been using trees for millennia. We ate the bark for medicinal properties, carved branches for spears and tools and statues, formed them into sleds and wagons and boats to carry us vast distances, hewed them down to make our homes. Every human culture on earth has had a use for wood. Learning to burn wood was the first hallmark in human evolution that led us to where we are today.
It’s no surprise that when we looked for tools to solve our climate connundrum, we looked to trees. But they may not be the solution we need… or want.
Trees are the solution to Climate Change…
…they say, and here is a short list of how.
Gluelam, Laminated Veneer Lumber, and Cross Laminated Timber can replace concrete in skyscrapers. Architects are smitten with the idea of using “renewable” timber products in low-carbon eco-friendly builidngs.
Forests are the go-to for governments looking to offset their emissions and meet UN climate goals. They’ve developed emissions trading schemes heavily weighted toward maintaining existing forests and growing new ones. The largest type of credits by far is forestry projects. The Rocky Mountain Institute estimates forests make up 44% of all carbon credits.
One of the easiest ways to replace fossil fuels like coal is by burning something else. We’ve been burning wood since the beginning, so wood was a no-brainer. This is known as biomass burning, and right now, biomass is hot. There are now over 100 biomass energy projects in the EU and the UK. Other coal fired power plants are interested because they can make a one-to-one substitution from coal to wood with very little investment or change in operations. In Japan, biomass makes up 5% of the country’s energy supply. South Korea is so smitten by biomass that they’ve reduced their budgets for other forms of renewables like wind and solar.
But there’s more. There’s biochar, where we replace fossil fuel fertilizers by burning trees down to charcoal in an oxygen-limited environment, with the added benefit of locking carbon in the soil. A New Zealand company called Futurity proposes breaking down pine trees to create a chemical resin to replace plastics and oil derivatives. There’s biomass burial — a company called Kodama received $6 million from Bill Gates’ climate fund to bury trees, locking away that carbon as securely as a peat bog. Just pruning vines off forest trees can increase the forest’s sequestration powers, and if that doesn’t work fast enough, a San Francisco firm called Living Carbon just got $36 million dollars to grow genetically modified trees. They absorb 27% more Co2 by growing 50% faster using genes from squash and algae, and they’re planting 5 million trees next year to prove it.
We have plenty of trees, right?
There are no shortage of solutions using trees, but no one seems to be asking if we have enough trees to bring those solutions to scale. Luckily, NASA used satellites and LIDAR to determine just how many trees we have available.
There are approximately three trillion trees on earth today. That sounds like a lot, but we have to remember there used to be more. Before human agriculture, there were twice as many, about six trillion trees. Humans removed 46% of all the planet’s trees since the dawn of agriculture, and half of that happened since 1900.
Before human agriculture, there were twice as many trees, about six trillion. 46% of them no longer exist.
That makes sense. There were only 2 billion people in 1900, while there are eight billion of us now. That’s a four-fold increase in people burning wood for fuel, using paper products, building timber houses.
So if trees can solve our problems, we’ll just make more of them, right? Let’s grow another three trillion trees. But there’s a problem. The land they need to grow on is where we farm food for humans. Trees compete with farmland and roads and cities and mining and every other land use we have, and in most cases forests and humans do not share.
Forests function best when they’re left alone, forever, and that just doesn’t work for us.
Of the forests we have left, 30% are farmed in rows as monocrops in the timber industry. 36% more are impacted by human activities — standing around our cropland, in our parks, beside our polluted rivers, subject to nitrogen runoff, ATV trails, arson, and lovers who carve little hearts and initials.
So pervasive has human intervention been that only about 34% of the world’s forests are primary forests, you know, the kind we think of when we hear the word “forest”. That’s 34% AFTER the 50% we’ve already removed.
That means 85% of the world’s original forests are currently serving human use.
Half of them serve us by no longer existing at all.
That list will grow. A recent paper published in Nature predicted timber use will grow by 54% by 2050. And you’re thinking, “Yeah, illegal logging is happening in those Global South countries because they’re desperate for cash”, where do you think that 54% growth will come from? It will come from countries like Europe, where barely any forests remain, yet their climate-forward environmentalists are somehow building eco-friendly skyscrapers and burning biomass to replace coal.
52% of the world’s forests are burned for wood fuel, and if that surprises you, you probably live in a rich country. Wood remains one of the world’s primary cooking fuels, especially in countries that still use coal. Do we really want to increase that number to replace coal?
The other 48% are used for wood products like timber, plywood, and paper. Again, do we really want to increase that with timber skyscrapers?
The truth is, whatever we use timber for, timber is not renewable. It is a finite resource, one that competes with all of our other resources, and one we’ve already half depleted.
It’s weird enough that we’re proposing more uses for timber as we have less of it available. But it gets weirder.
The lungs of the world have COPD
You’ve known since grade school that humans breathe in oxygen and expel carbon dioxide while trees photosynthesize carbon dioxide and expel oxygen. That’s why rainforests are called the lungs of the world. If trees are the lungs of the world, we already cut out one lung, and the remaining lung has only 15% of its natural capacity, the rest riddled with cancer from our fossil-fuel smoking habit. The lungs of the world have COPD and hypercapnia.
But, and this includes me and I’m ashamed to admit this, we rarely think about what trees do with that CO2. It’s absurdly simple. They keep the C and release the O2. They use carbon to build the tree, the branches, the leaves, and even share carbon through their roots with other trees and symbiotic organisms in the soil.
Trees don’t “sequester” carbon in the context we use it for climate change. They use carbon to build themselves. They’ve been doing it for millions of years, long before humans and their fossil fuels even existed.
Every life form on earth uses carbon. Life on earth is carbon based.
There’s another carbon based life form that uses carbon to build itself. Humans. Right now your body is using carbon to build proteins, carbohydrates, and fats. It’s our prime energy source.
But we would never phytomorphize humans by saying humans sequester carbon. Why? Because we don’t get carbon from the atmosphere, but from the plants we eat, who do.
We never used to think about plants sequestering carbon until we had so much carbon to get rid of. Suddenly, we’re looking at which species use the most carbon to build themselves and which species build themselves the fastest. It’s like we’re scoping out locations for a landfill.
I mean, if you spill something on your kitchen counter, you reach for a plant-based towel to soak it up. Well, we’re spilling a lot of carbon in the atmosphere, and rather than paper towels we’re talking about using whole ecosystems.
Even environmentalists look at trees as a sponge.
When you see it like this, you realize so many of our attempts to use trees are absurd. I mean, all they’re doing is using carbon to make more tree. It’s as absurd as saying humans could solve climate change by eating more food, or paying people to make babies and populate less dense regions, or proposing we solve climate change by genetically engineering humans to grow taller or faster, or saying that cremation is climate neutral. Maybe the only thing saving us from this fate is that we’re only 18% carbon whereas trees are 50%. But don’t feel safe just yet. Humans are made up mostly of water, and we can use that to make hydrogen — to burn.
Ecosystems are not climate sinks for excess carbon. Trees can only grow so tall, plants can only grow in certain biospheres, ecosystems can only support so many species. We know this because that’s what a climax system is. It’s a forest that has almost stopped absorbing carbon as it reaches its maximum capacity. And again, that doesn’t work for us.
The ideas that we’re pushing to make more, to use more, to burn more, to bury more are such consumerist concepts. They’re anathema to all environmental beliefs and scientific understanding, but it’s environmentalists and scientists proposing it.
That’s weird.
Even weirder, trees as we know them first developed during the Carboniferous period 300 million years ago, so called because those trees became the coal that we burn today. All we’re really doing is asking modern trees to replace fossil trees. We’re expecting them to absorb the carbon we released by burning their fossilized ancestors.
The next million years
What the forest needs is to recover. But our culture is one of consumption. If a person stops using something, someone else starts. The moment a farmer sets aside his field for a timber stand, an architect eyes it up as a building material. No sooner does a branch fall on the forest floor, than someone collects it for a fire. And if you think those newly minted carbon sinks are going to just sit there without anyone using it, think again. For every tree in a carbon sequestration programme, there’s a power plant gearing up to burn it.
Forest biodiversity? Farmers are fencing off native forests to prevent deer from browsing on the undercarriage because that would diminish the carbon capture value of the forest.
Looking at nature through the single lens of carbon blinds us to the complexity and interdependency of nature. It ignores biodiversity. It ignores soil suitability. It ignores ecosystems. It ignores weather patterns created by natural and unnatural growth. It ignores pretty much everything that does not include a carbon calculation and by extension a monetary value.
We’re treating forests like crops. In fact, one company here in New Zealand has the name Carbon Crop.
Carbon Crop.
You can’t make this stuff up. We are literally growing crops to sequester carbon. As if we have plentiful land and resources to grow trees AND food.
But trees don’t just store carbon. Leaves fall off. Nuts fall off. Branches fall off. Even trees fall down when wind and rain and time take their toll. Each of those are carbon returning to the system, where bacteria break it down and return it to either the ground or the atmosphere. Forest fires burn up the detritus to clean up a forest, a process which can even be essential for some trees to reach maturation and spread their seeds.
Are we proposing to stop all that? Will we genetically modify trees to never break, never seed, never reach autumn? Will we breed a globe of Radiata pine?
Old growth forests are called a climax community because they have reached maximum growth. Without growth, they don’t take up carbon. That makes old-growth forests a liability in climate change. They’re worth more dead than alive, not just in economic terms, but in carbon sequestration. How long till we’re desperate enough that we tear down old forests to plant new, genetically modified, carbon absorbing trees? Because desperate people are already discussing it. If it weren’t for protections, this would be happening already.
It some ways, it already is. Just this year, thousands of hectares of New Zealand’s more marginal sheep farms have converted to growing pine because the carbon credits pay better than wool. Indonesia’s logging company Medco cut down 170,000 hectares of old growth forest for the specific purpose of growing new trees for biomass in the country’s electricity production, allowed to do so because it was a move away from fossil fuels. In Chile, paper mills built boilers they didn’t need, burning biomass for electricity they could sell for carbon credits. That biomass is trees.
As the price of carbon goes up, farmers everywhere are replacing farms with trees, just as they once replaced trees with farms. But land can only be used for one thing, and the knock-on effect of this conversion from farm to forest will be felt in a world increasingly pressured for human food production.
Think that’s a good thing? What happens when we finish electrification and the carbon price dives. Forget 50 year carbon sequestration. Those same farmers will be felling those trees with electric chainsaws, and we’ll see a spike in biogenic carbon like never before. Unless they bury that forest in an anaerobic landfill like the worthless trash it’s become.
How unnatural are we willing to make nature in order to clean up our mess? More correctly, how much MORE unnatural than the 85% we already have.
This obsession of ours for the regenerative beauty of trees, this timberpunk view of returning to a yesteryear we’ve long since depleted, this puerile faith in nature to clean up our adult-sized mess, our love of forests may yet be the end of them.
We need solutions that don’t involve trees.
The solution to the solution
We could just say — leave trees alone, but that’s not much different than the other failing phrases shouted at the UN to just leave oil in the ground. We must recognize the massive status quo at work and the long timelimes involved to tackle them. The solution here is no different than the solution to climate change. Replace, remove recover. In fact, solving the problems of climate change can also regenerate the forests so long as they don’t serve us.
If we were serious about carbon sequestration, we’d be planting trees that absorb the most carbon, trees like the gnarly live oak or East Palatka Holly. But we don’t because there is no established market for these the way there is for the pine trees that make up nearly all our commercial forests. So carbon offsets are nothing more than a way to support existing forestry. We love pine trees. They’re the only tree that bridges the gap between conservationists and capitalists. Neither of them want to cover the earth in Holly.
Because they’d have to. Depending on the species, trees store about 25 kilograms of CO2 each year, and in 2022, as a species, we planted 52 million trees, capturing 1.3 million tons of CO2. We’re 10% of the way to emptying one day’s worth of bathtub water. We’ve done two hour’s worth of work.
Forests are not carbon sinks
All the forests in the world only absorb 7.6 billion tons of carbon a year. Most of that is the natural, biogenic CO2 that the earth’s ecosystems make…. without our excess anthropogenic sources. if we could somehow get them to focus on only our anthropogenic sources, they would still only soak up 20% of our annual emissions. The World Resource Institute found that with all the trees we’ve planted in the last 20 years, they only sequester an additional 5% of our carbon.
Realistically, we’d have to grow one and a half trillion trees, roughly equal to four Amazon rainforests, one quarter of all the trees on the planet, every year, until we run out land, in order to have any hope of offsetting our emissions. That means trees to the exclusion of all else — food, mining, housing, everything that is not a tree. And that does nothing to stop climate change or cease our emissions. It just stalls it for a while.
It’s baffling why we even have trees on the menu if they’re coming up more than 80% short every year. Our faith in trees to sequester carbon is absurd. It does nothing to solve climate change.
In order to protect our remaining forests, we need to replace trees in our global supply chain, especially the trees we haven’t yet found a use for. We’ve done it before. We replaced ttrees with cement and oil and plastics. Now we need to do it again.
We can replace cement with zero carbon alternatives so we don’t have to use timber. We can stop burning anything by getting our power from renewables like wave energy. We can replace half of our current timber just by getting the world on electric cooktops. These solutions exist today. We don’t need timber to solve our climate problems.
But the biggest replacement we can make is in our mindset. We need stop looking at nature as a renewable resource and see it for the finite and closed system it is. The next time you’re looking for a low carbon alternative, don’t look at trees. Don’t ask nature to solve this for you.
Eulogy
There is one thing everyone got right about forests. We need more of them. Forests, not forestry. We need to plant more trees, allow existing forests to expand, let them become not just a hectare of trees but an ecosystems again, and stay out of their way.
If you want to make a difference, contact the Rainforest Action Network to see how you can protect a forest, not for carbon credits, but for survival. Talk to your local Climate Change Commission to treat biomass the same way we treat coal. Tell your local Emissions Trading Scheme to divorce forests from carbon, forcing funds to be spent on anthropogenic solutions to anthropogenic emissions.
But more than anything else, when you think of the word replace, don’t find a use for trees.
So long as we treat nature as a product, something we only value when it can be bought or sold or traded or buried or burned, we will never recover.
If you’re serious about solving climate change, listen to more great ideas on the podcast Replace Remove Recover, available on Spotify or wherever you get your podcasts.
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