During our planting events, the question we are asked most often is almost always the same: “Which trees capture the most CO2?” This is often accompanied by a doubt: why don’t we plant fast-growing species such as paulownia or ailanthus?   Answering this question is not as straightforward as it seems. While it is true that planting trees is one of the fundamental strategies for combating the climate crisis, focusing solely on the amount of carbon dioxide sequestered is a technical and strategic error. Trees are not simply carbon sponges: they are complex organisms that live in delicate ecosystems. The…