Mr. Beast’s and #TeamTrees’ reforestation push, the “trillion tree campaign” from Plant-for-the-Planet, the Bonn challenge, the Great Green Wall, the New York Declaration on Forests, and many other, similar efforts are gaining traction at an unprecedented rate – not least because scientists are saying that reforestation is a top climate change solution. This raises an urgent question: how can we tell the difference between trees that protect the future of our planet, and those that are actually making the climate crisis worse?

One of the biggest lies of our times is that planting trees is simple. In fact, there’s so much that can go wrong: if you plant monocultures instead of mixed forests, you end up with ecological dead zones. If you plant non-native species, they could become invasive and end up destroying biodiversity. If you don’t partner with local communities, your trees won’t survive at all.

In short, not all tree-planting is equal. But it’s easy to tell the difference between sustainable and destructive tree-planting, once you know where to look.

If you don’t have time to watch this episode of “Behind the Picture” (above), here’s a summary of what you should ask next time someone claims to be planting trees:



Have the trees actually been put in the ground? Are they being monitored or are we dealing with a feel-good, but ultimately unrealistic pledge? Are local communities equal partners in the project? Do the trees benefit them? Will they take care of the trees? Are the tree species native to the area, or are they imported and maybe even invasive? Have they planted a mixed forest or a monoculture?

For reasons of accessibility, we also include a transcript of this video:

When you look at a forest, what do you see? When I was in Kenya last August, I saw two different realities. I walked into forests that were cool and humid, where I could hear insects and birds, small things singing. But only a short drive away, I found myself surrounded by trees that seemed hostile to life. There were no streams and the birds had left. And I started thinking: These days everyone is planting trees. Or claiming to do so. But how can we tell the difference between trees that protect the future of our planet, and those that are actually making the climate crisis worse?

One of the biggest lies of our times is that planting trees is simple. In fact, there’s so much that can go wrong: if you plant monocultures instead of mixed forests, you end up with ecological dead zones. If you plant non-native species, they could become invasive and end up destroying biodiversity. If you don’t partner with local communities, your trees won’t survive at all.

In short, not all tree-planting is equal. But it’s easy to tell the difference between sustainable and destructive tree-planting, once you know where to look.

This is not a forest. This is not a forest either. Both are monocultures, industrial tree plantations of one and the same species, green deserts. One thing you notice when you walk into a monoculture is that the soil is hard, and the air is silent. Monocultures harm biodiversity, because they don't provide the necessary range of food, shelter and nutrients for life to thrive in all its variety.

Monocultures are usually planted to produce cheap timber, rubber or palm oil. These products are generally exported to fuel industrialized countries, leaving their true costs behind: ecological degradation, water contaminated with pesticides, depleted soil, and unfair labor conditions. Since the 80s, these tropical tree monocultures have expanded by almost fivefold. Which is bad news in terms of climate change, too.

While mixed forests store massive amounts of carbon, especially as they age, tree monocultures often emit carbon. This is because they disturb the soil and because plantations tend to be grown where ancient forests once stood.

Don't get me wrong: there are some uses to monocultures. For instance, it's often a good idea for farmers to have a small woodlot instead of getting their timber from a natural forest. But bigger monocultures are almost always destructive.

In Indonesia, the conversion of primary forest into monocultures is particularly striking. In the last 30 years, a quarter of the country's forest cover has been sacrificed on the altar of cheap palm oil. Here's how it usually goes: multinationals move in, buy land off smallholder farmers, cut down huge tracts of natural forest to make room for palm tree monocultures, which they then cover with copious amounts of pesticides and fertilizers. When the soil is completely depleted after a couple of years, the companies move on to other areas of the rainforest. In short, they treat the Earth as if it was a supply house and a sewer.

Despite all this, international institutions like the UN's Food and Agriculture Organization, the World Bank, as well as a bunch of government agencies define monoculture plantations as forests. Which is, well, a lie.

You might have guessed it: we're not massive fans of large-scale tree monocultures. Whenever Ecosia plants a forest, we make sure to plant a range of different species that help one another store carbon, regulate the water cycle, restore nutrients to the soil, and promote biodiversity. Like this one we planted in Indonesia on a former plantation. Or this one we planted in Brazil on degraded farmland.

So next time someone claims to plant trees, ask them: are you planting mixed forests or monocultures?

But it's not enough for a forest to be diverse. The species that are planted matter, too.

When you plant European or Australian trees in sub-saharan Africa, you're going to throw delicate ecosystems out of balance. These imported species are sometimes invasive, displacing the native species, depleting water levels, and suppressing biodiversity. We therefore prefer to plant native trees, especially those that have become rare. These species have had millions of years to adapt to their local environment, and they’ve become very good at it.

So next time someone claims to be planting trees, ask them if they are planting mixed forests or monocultures; native species or imported ones.

But there's something else you should take into consideration when you plant a tree – something that most tree-planting projects forget: people! Not enough reforestation projects deal with the fact that the land they intend to plant on is being used. Planting trees and then leaving forever is bound to fail. The trees rarely survive, and if they do, they'll probably be cut down again.

A better strategy is to put local communities first. It's not just the right thing to do, it’s also necessary for forests to grow back. When local communities have a better quality of life, the financial pressure to sell their land to mining companies, loggers, or big agribusinesses disappears. And when their improved quality of life is directly linked to tree planting, they have a powerful reason to protect these trees, and to plant even more of them.

So how can you make sure that trees benefit local communities?

In many cases, the trees Ecosia plants provide valuable tree products, such as baobab powder, shea butter, fruits, or Tengkawang oil, just to name a few. Consuming and selling these products is, in the long run, much more profitable than cutting the trees down.

Trees also have a positive effect on smallholder farms. They improve soil fertility, prevent erosion, clean and replenish water supplies, and create microclimates that have become a vital resource on a warming planet.

So next time someone claims to be planting trees, ask them if they are planting mixed forests or monocultures, native species or imported ones. And ask them it they are engaging local communities at eye level, or just dumping saplings, hoping for the best.

But there's one last thing. In the first few years of their lives, trees are very delicate. So it’s important to care for them and keep track of them. To have a database that tells you exactly where they are, and whether they’ve survived. We track our trees for at least three years, using satellite technology, a monitoring app, geotagged photos, independent auditors, and field visits. In case some of the trees we monitor die, we subtract them from our tree counter.

So, you get the idea. This work is pretty damn complex. But we don’t really have a choice. We have to get it right. More and more scientists are saying that reforestation is a top climate change solution. So the next time someone claims to be planting trees, give ‘em a high five. And then ask them:

One. Have the trees actually been put in the ground? Are they being monitored or are we dealing with a feel-good, but ultimately unrealistic pledge?

Two. Are local communities equal partners in the project? Do the trees benefit them? Will they take care of the trees?

Three. Are the tree species native to the area, or are they imported and maybe even invasive?

And finally, four. Have they planted a mixed forest or a monoculture?

On another day in Kenya last August, I met Kiberenge Moraia. He’s 85 years old, and grew up in an intact, native forest. He told me about playing in the river as a child. But in the seventies, a government agency replaced that forest with a pine tree monoculture. Soon after, the river ran dry.

Now, his community is planting native species with us. And the water -- it’s coming back.

So no, planting trees is not simple. It’s complex. It’s hard. But when it works, it’s also magnificent.