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Abstract Post‐fire stand water balance is a critical factor influencing tree regeneration and survival, which are often modulated by fire severity. We examined influences of the post‐fire vegetation matrix and fire severity on diurnal, seasonal, and multi‐year variation in evapotranspiration (ET) by analyzing the relationship between post‐fire vegetation and ECOsystem Spaceborne Thermal Radiometer Experiment on the International Space Station (ECOSTRESS) ET data using multivariate and linear mixed effects modeling. Unlike many high‐severity fire sites where ET drops after burning, post‐fire ET was high at shrubland sites that burned at high fire severity in southern Arizona, USA. In this study, post‐fire ET was driven by plant species composition and tree canopy cover. ET was significantly higher in the morning and midday in densely vegetated post‐fire shrublands than pine‐dominated forests that remained 5–7 years after wildfire. Our results demonstrate that plant functional traits such as resprouting and desiccation tolerance drive post‐fire ET patterns, and they are likely to continue to play critical roles in shaping post‐fire plant communities and forest water cycling under future environmental change.

Abstract The long‐term outcome from accelerated forest restoration using resource objective wildfire in combination with fuel management on fire‐excluded landscapes is not well studied. We used simulation modeling to examine long‐term trade‐offs and synergies of alternative land management strategies by combining two wildfire management alternatives with three levels of contemporary forest restoration treatments on a 778,000‐ha landscape over 56 years. We found that managing wildfires for resource objectives diminished the likelihood of irregular fire events over time by making wildfire activity more predictable. Overall, adding resource objective wildfire reduced the proportion of high‐severity fire in relation to total area burned, but increased total area burned and the area of high‐severity fire. We also found resource objective wildfire changed the distribution of high‐severity burn patches by increasing their total number and range, their likelihood of containing disjunct core areas, and their edge complexity. The results suggested that alongside the current pace of active forest management, expanding the fire footprint to achieve low‐cost restoration carries the potential for increased high‐severity fire and associated impacts to ecological values including old forest structure and wildlife habitat. Concurrently, adding resource objective wildfire expanded the footprint of conventional restoration treatments by fivefold, and restoration objectives were achieved in 25 years when managing resource objective wildfires alongside restoration treatments five times the current pace. This study demonstrates the first fire suppression model to replicate local decision making by fire managers during simulated fire events to manage risk by considering both fire proximity to values at risk, and daily weather conditions. The study paves the way for further investigations of the synergies between wildfires and conventional forest restoration to improve resiliency in fire‐excluded pine forests.