Reforestation is the practice of planting trees on land that has been forested. It is one of the most effective ways to improve the health of forests and the environment, and has been shown to help slow climate change. But reforestation can also have a significant impact on local communities and the larger ecosystem. Done incorrectly, reforestation can even speed up species extinctions and harm the environment in the long term.

Last year saw billions of trees planted in hundreds of countries around the world as people came together to restore forests and combat climate change. The scale of planting was unprecedented, with millions of trees being planted in a single day. This widespread effort is a sign of growing awareness about the importance of forests and their role in fighting climate change.

Reforestation efforts are booming all over the world, with governments, businesses, and individuals all committing to planting trees. But planting trees is an intensive activity, and when done improperly it can have a serious impact on the surrounding ecosystem. In some cases, reforestation efforts have actually resulted in forest fragmentation, a decline in biodiversity, and even the extinction of species that were not native to the area. This is largely due to the fact that planting the wrong species in the wrong place can actually reduce the amount of biodiversity in an ecosystem, speeding the extinctions of species that couldn’t adapt and making ecosystems far less resilient.

The world was in crisis. The planet was warming, its ecosystems were being degraded, and biodiversity was being lost at alarming rates. The crisis has been dubbed climate change, but the crisis is actually biodiversity loss — a global phenomenon that is akin to climate change in its severity and is getting worse. Extinction rates are surging, and many species are on the brink of vanishing forever.

“You’re creating basically a sterile landscape” said Paul Smith, the executive director of Botanic Gardens Conservation International, an umbrella organization dedicated to preventing plant extinctions. “Let’s make it a positive for biodiversity if people wish to plant trees.”

In the field of tree planting, there is a rule of thumb: “Plant the right tree in the right place.” “For the right purpose” some add.

People typically disagree on what “right” means, according to discussions with a range of participants — scientists, policy experts, forestry firms, and tree-planting NGOs. For some, large tree farms for carbon storage and wood are the answer. Fruit plants are provided to small-scale farmers by others. Others, though, see it as a means of allowing native species to recover.

planting trees

Bad actors

Trees are a vital part of the planet’s ecosystem — and when they’re planted in the right place, they can do even more. Trees store carbon, which helps fight climate change. They provide habitat for wildlife, clean the air and water, reduce flooding, and even make cities more beautiful. But different species of trees provide different benefits, which is why it’s important to choose the right tree for the right place.

Eucalyptus, for example, grows quickly and straightly, making it a valuable timber resource. Its leaves, which are native to Australia and a few islands to the north, provide food for koalas, who have adapted to survive a strong toxin in the leaves. However, the trees give significantly less benefit to animals in Africa and South America, where they are commonly planted for lumber, fuel, and, increasingly, carbon storage. They’re also being accused for diminishing water supplies and exacerbating wildfires.

The same species everywhere

According to a recent estimate, approximately 60,000 tree species exist on the earth, with around a third of them being threatened with extinction due to agriculture, grazing, and exploitation. According to tree planting organizations and experts, only a small percentage of species are widely planted globally.

“They’re planting the same species all over the world,” said Meredith Martin, an associate professor of forestry at North Carolina State University, who discovered that in the tropics, charity tree planting programs emphasize people’s economic requirements above biodiversity and carbon storage. According to her, these attempts risk diminishing forest biodiversity over time.

planting trees