Planting a trillion trees might be the only thing Donald Trump and Jane Goodall don’t disagree about. The global initiative to plant and conserve one trillion trees over the next decade aims to limit the impact of greenhouse gas emissions. This sounds like a great idea. But, to quote Greta Thunberg, it is “nowhere near enough” – it cannot, in other words, become an excuse not to cut emissions. Here’s what you need to know.

Why planting a trillion trees will mitigate climate change



Trees are having a moment, and that’s good news for the planet. Planting forests (and protecting the ones that still remain) is a natural, cheap and effective way to capture significant amounts of heat-trapping CO2. And doing so is essential to prevent dangerous levels of global warming.

Trees have many other benefits, too: they provide a habitat for animals, regulate the water cycle, restore nutrients to the soil, increase biodiversity, and provide local communities with forest products such as fruit and nuts. That’s why at Ecosia, we use our profits to plant trees.

But we also build solar plants and support regenerative agriculture, because we know that climate change mitigation requires a reduction of greenhouse gas emissions, not just carbon capture.

Not all tree planting is equal: how to get tree planting right



Planting trees protects the future of our planet – provided it’s done in the right way. Otherwise it can actually make the climate crisis worse. Planting monocultures instead of mixed forests leads to ecological dead zones – and certainly doesn’t offset emissions. Non-native species and invasive tree species destroy biodiversity. And without the buy-in and support of local communities, trees don’t survive for long.

It is not clear, at this point, whether the one trillion trees campaign will take these complexities into account. Which species will be put in the ground? How will the initiative protect them? Will the campaign work with local communities, especially indigenous groups who depend on forests? One trillion trees require a lot of space. Where will the trees be planted? Is that land currently being used, e.g. for agriculture?

Planting trees is no excuse to emit more CO2



In order to avoid irreversible feedback loops, global warming mustn’t surpass 1.5 degrees Celsius. And in order to stay below 1.5 degrees, we must cut emissions now.

My gap year ends in August, but it doesn’t take a college degree in economics to realise that our remaining 1,5° carbon budget and ongoing fossil fuel subsidies and investments don’t add up. 1/3 pic.twitter.com/1virpuOyYG — Greta Thunberg (@GretaThunberg) January 23, 2020

Planting trees sequesters carbon and helps us adapt to the effects of climate change. But it doesn’t replace the need to cut emissions. A trillion trees, if planted today, would take decades to reach their CO2-absorbing potential. They cannot instantly neutralize the emissions that are currently being emitted.

Does the trillion trees campaign provide an excuse to keep up emissions?



The trillion trees campaign runs the risk of helping businesses and governments to reap the PR value of climate action without reducing their emissions. Planting trees is not a substitute for the changes these businesses and governments need to make in order to prevent greenhouse gases being emitted in the first place.

President Trump is a good example. He mentioned the trillion trees campaign at Davos and during his State of the Union address. At the same time, he referred to climate activists and scientists as “prophets of doom”, encouraging his audience not to divest from coal and other fossil fuels. At his State of the Union address, meanwhile, he didn’t mention climate change at all. During his time in office, he has rolled back regulation to reduce emissions, and has opened the Tongass National Forest, America’s largest natural carbon sink, to logging. In this light, the trillion trees campaign starts to look like an effort to deflect calls for the kind of regulation and investments needed to cut emissions, e.g. by keeping fossil fuels in the ground.

In short, it’s a bit more complicated than it might appear at first sight. Planting and protecting trees is essential. We cannot face the climate crisis without doing so. But these trees need to be planted in the right way, and they certainly don’t provide an excuse to keep emitting greenhouse gases.