Congratulations to Rose Mohammadi on having her paper on groundwater and riparian tree phenology published in Global Change Biology! We found that willows, cottonwoods, and valley oaks along Chalone Creek (Pinnacles National Park, CA) responded strongly to the historic 2020-2022 drought. By combining satellite and groundwater data, we found that trees along intermittent streams shortened their growing season by up to 5 weeks during droughts: nearly twice the shifts seen in global datasets. These trees might regularly experience these dry spells, but our findings suggest they’re operating dangerously close to their groundwater limits as droughts intensify.