An image fusion approach was developed to downscale ECOSTRESS evapotranspiration (ET) products from a spatial resolution of 70 m to 10 m and enhance their temporal resolution to daily estimates. Remote sensing-based algorithms were created by correlating ECOSTRESS Level 3 data with in-situ ET measurements from eddy covariance flux towers, enabling ET estimation in non-instrumented areas. The study utilized data from 10 flux tower sites spanning three forest types—loblolly pine, longleaf pine, and deciduous hardwood—to calibrate and validate the algorithms. The resulting high-resolution ET estimates support fine-scale ecohydrological assessments and improve monitoring of vegetation stress in heterogeneous forest landscapes.