Gayoung Yang, Constantin M Zohner, Gabriel Smith, Wilma Blaser-Hart, Christian Dupraz, Sima Fakheran, Adrian González-Chaves, Amy Ickowitz, Shibu Jose, Sonja Kay, Yuting Liang, Daniel Maynard, Kaline de Mello, James Reed, Jo Smith, Terry Sunderland, Achim Walter, Yuki Yamamoto, Lewis Ziska, Thomas W Crowther

Balancing forest conservation and agricultural production is essential for a sustainable future. Here we review the scientific evidence for the relationships between forests and agricultural productivity across different scales, summarizing the contexts under which trees limit, maintain, or enhance agricultural productivity. While synergies and trade-offs occur at local scales, a regional-scale meta-analysis reveals mostly positive effects of forests and average national-level agricultural productivity is projected to decline once forest cover loss exceeds ~48%, with a 95% confidence interval [44, 50]. Given that 70% of countries have already reached or exceeded this threshold, implementing targeted forest conservation and restoration policies may be critical to optimize national food security. At a global scale, mass deforestation remains a key threat to international food production.