The relationship between productivity and species richness is one of the most widely documented patterns in ecology and yet the mechanisms determining this pattern are not well understood. Over the past decade, Dr. Gross has been involved in research that has tried to address this question using 1) synthesis of data from nutrient addition experiments from a wide-range of ”˜grasslands’ across the USA and 2) experimental studies in low productivity grassland where the heterogeneity of nutrient additions was manipulated. These analyses have shown that while there is an overall negative impact of nutrient enrichment on species richness in grasslands, the magnitude differs across communities and functional groups. Results from more recent analysis and a long-term field experiment reveal that the presence of species with specific growth form traits, specifically rhizomatous clonal growth and height, may be important in driving the magnitude of species diversity loss in grasslands. The ongoing goal is to determine why communities and species respond differently to nutrient addition and to use this to develop ways to maintain and conserve native plant diversity in grasslands being used for a variety of ecosystem services.