Estimating site quality for a specific tree species is an important tool in forest management. While intensively managed pine species are often the focus of site quality studies using site index, hardwood species found in bottomland hardwood sites are often lacking in quality growth prediction equations. Two valuable hardwood species, willow oak (Quercus phellos) and cherrybark oak (Q. pagoda), are of interest for forest managers of east Texas bottomland sites. The objective of this study was to develop site index prediction equations and curves for these two species. Using height and age data from 267 cherrybark oaks and 460 willow oaks collected from sites across east Texas, remarkably similar equations were developed, with coefficient of determination (R2 ) of 0.63 for cherrybark oak and 0.52 for willow oak