Planting trees has become one of the most recognisable responses to climate change. Yet adding forests to every available landscape may do more harm than good.

Environmental research highlights why successful restoration depends on understanding local ecosystems, protecting existing biodiversity and recognising that naturally open landscapes have their own important role in regulating the climate.

Why More Trees Aren’t Always Better

Large-scale restoration programmes have ambitious environmental goals. The Bonn Challenge, for example, aims to bring 350 million hectares of degraded and deforested landscapes into restoration by 2030. However, restoration does not necessarily mean covering every landscape with trees.

Grasslands, shrublands and savannas are sometimes mistaken for degraded environments because they lack dense vegetation. In reality, many are ancient ecosystems that have evolved to survive drought, unpredictable rainfall and challenging growing conditions.

Introducing extensive tree cover into these landscapes can disrupt established habitats, threaten native species and place additional pressure on already limited water supplies.

The Hidden Cost Of Planting

Trees absorb carbon dioxide, but their environmental impact extends beyond carbon storage.

In dry regions, large-scale planting can increase competition for water. Unsuitable tree species may reduce streamflow, affect groundwater reserves and leave less water available for agriculture and surrounding communities.

There is also a less obvious consequence involving sunlight. Open grasslands and pale soils often reflect more solar energy than darker forest canopies. Replacing them with trees can reduce this reflectivity, known as albedo, potentially offsetting some of the cooling benefits gained through additional carbon absorption.

Consequently, planting trees in unsuitable locations may deliver fewer climate benefits than expected, even when the trees grow successfully.

Learning From Africa’s Drylands

Africa offers valuable examples of why restoration needs to reflect local environmental conditions.

The Great Green Wall initiative, launched in 2007, originally envisioned an extensive belt of trees across the Sahel to combat desertification. Its approach has since evolved towards broader landscape restoration, sustainable agriculture and community resilience.

In Niger, farmers have successfully restored approximately five million hectares through farmer-managed natural regeneration. Rather than relying entirely on newly planted seedlings, they protect and manage native trees and shrubs that regrow from existing roots, stumps and seeds.

This approach can improve agricultural productivity while supporting vegetation already adapted to the region’s climate.

Rethinking Climate Action

Tree planting remains valuable where forests have been destroyed and suitable native species can thrive. The problem arises when planting targets become more important than the ecological consequences.

Effective restoration should be measured through healthier soils, stable water supplies, thriving native species and improved local livelihoods rather than simply counting newly planted trees.

Protecting the planet does not always require creating more forests. Sometimes, the most meaningful environmental progress comes from recognising the value of landscapes that are already functioning exactly as nature intended.