A new study shows that photosynthesis in tall Amazonian forests — forests above 30m — is 3x less sensitive to precipitation variability than in shorter forests of less than 20m. Taller Amazonian forests were also found to be older, have more biomass and deeper rooting systems that enable them to access deeper soil moisture, making them more resilient to drought. The findings suggest that forest height + age are an important regulator of photosynthesis in response to droughts.