… maybe they aren’t quite that black-and-white about it, but … trying to plant our way out of global warming is going to have some so-far-underappreciated side effects. Planting trees to absorb carbon and reduce the threat of climate change could cause a range of new environmental problems. … tree plantations can dramatically reduce water availability, remove nutrients from soil and increase its salinity. … better planning is needed to assess the environmental costs and benefits of planting trees to mitigate climate change. … it is important to think carefully about where and what people plant, particularly where water resources are scarce.