Full article: https://science.sciencemag.org/content/365/6448/76 (paywalled; SciHub link: https://sci-hub.tw/10.1126/science.aax0848)
Key quote: "The most effective projects are doing restoration for 30 US cents a tree. That means we could restore the 1tn trees for $300bn [£240bn], though obviously that means immense efficiency and effectiveness. But it is by far the cheapest solution that has ever been proposed."
Forest-related charities (CoolEarth et al.) have already received a good bit of attention in the past, but if these new findings are true, then perhaps we have been underestimating the benefit of reforestation, and should be directing more funds towards them?