Body of Abstract: Plants are constantly dealing with environmental changes. Drought is one of the most significant environmental stresses that affect agriculture yield. Leaf cell division and cell expansion inhibitions under drought represent a possible opportunity cost for plants grown in unpredictable environments; reduced leaf area limits future carbon assimilation. This study compared the growth inhibition of three cereal crops (oat, barley, wheat) and their progenitors, as well as their wild grass relative Brachypodium under drought. As expected leaf growth responds differently across species under drought, shown as final leaf length and leaf elongation rate. Using microscopy and machine learning, we are able to identify epidermis cell size profile along the leaf axis to characterize cell division and elongation parameters. This allows us to evaluate the relative roles of cell division and cell expansion in limiting leaf growth under environmental stress. Based on their diverse responses under drought, the goal is to identify molecular mechanisms related to leaf growth inhibition as a response to drought. Future experiments will characterize how the mechanisms are related to drought acclimation and resistance, with the goal of improving crop drought resistance.