Ecologists are interested in conducting cross-site or large-scale integration and analysis of annual aboveground net primary productivity (ANPP) values, but are often hindered by the lack of standard methodologies for data collection, data management practices and detailed metadata documentation across sites. The Grasslands ANPP Data Integration (GDI) project has brought together experts in ecology, information management, and computer science to address the challenges of integrating ANPP data and create a centralized database. The integration of species-coded data between sites proved to be a major component of the work and revealed a number of common problems. Based on our experience, we have developed a number of suggestions for managers of any species-coded database to minimize the problems of cross-site integration and concise examples that convey the problems facing all integrators of species-coded data. This poster suggests guidelines for species data formats, reclassifying species or combining indistinct species, correlating species lists across sites, and referencing standard species lists such as the US Department of Agriculture's PLANTS database. These techniques are especially important for long-term, ongoing, or integrated datasets.