China has invested more resources than any other country in reversing deforestation and planting trees. However, given the large scale of these programmes it has been difficult to quantify their impact on forest cover. A new study shows that much of China’s new tree cover consists of sparse, low plantations as opposed to large areas of dense, high tree cover. The results of the study could help policymakers track returns from tree-planting investment and identify suitable environments for future afforestation, aiding efforts to sequester carbon, prevent soil degradation and enhance biodiversity.