USDA
USDA/ARS/NSTL
The National Soil Tilth Laboratory is one of USDA-Agricultural Research Service's network of research laboratories across the United States. NSTL is unique in its efforts to address the interaction between agricultural management practices and the resultant effect on environmental and soil quality. This interdisciplinary laboratory conducts research that builds on understanding the processes (laboratory and plot scale) up to watershed and regional scale assessment and application. Website: "http://www.nstl.gov/" [Summary provided by the USDA.]