Too much reforestation will make food unaffordable, Oxfam warns.

Governments and businesses hoping to plant trees and restore forests in order to reach net-zero emissions must sharply limit such efforts to avoid driving up food prices in the developing world, the charity Oxfam has warned.

Planting trees has been mooted as one of the key ways of tackling the climate crisis, but the amount of land needed for such forests would be vast, and planting even a fraction of the area needed to offset global greenhouse gas emissions would encroach on the land needed for crops to feed a growing population, according to a report entitled Tightening the net: Net zero climate targets implications for land and food equity.

At least 4 billion acres—an area five times the size of India, equivalent to all the land now farmed on the planet—would be required to reach net zero for the planet by 2050 via tree-planting alone. While no one is suggesting planting trees to that extent, the report’s authors said it gave an idea of the scale of planting required, and how limited offsetting should be if food price rises are to be avoided.