Coastal forests are at risk of ecosystem level collapse due to saltwater intrusion causing forest mortality. Sudden die off events such as those resulting from storm events have been well documented, however the effects of progressive and chronic salt stress on coastal forest health is less known. This study investigates the effects of salt stress in two US Atlantic coast maritime forest tree species, loblolly (Pinus taeda) and slash (Pinus elliottii) pine, occurring in a brackish marsh and an upland grassland. We investigated leaf-level physiology traits (e.g. photosynthesis) and leaf photochemistry to understand how salt impacts tree health. Additionally we conducted stand surveys of mature trees to understand community dynamics. Our goal was to understand how differences in species salt tolerance could alter forest succession under salt water intrusion scenarios. Our results lead us to suggest that as salt stressed forests begin to thin and retreat, regenerating saplings may not be able to capitalize on the resulting increased light environment leading to mortality before reaching replacement age. This study helps us better understand how coastal forest dieback exacerbates the effects of sea level rise.