Evaluation of pasture characteristics, such as herbage mass, and species composition, may be a laborious and time-consuming task.  Statistics of pasture variables are derived from sampling procedures but little attention is given to the spatial distribution of production  variables, especially in large scale systems.  High resolution NDVI (normalized difference vegetation index) data collected with ground-based, aircraft, or satellite-carried remote sensing devices may be used to assemble databases for the spatial and temporal definition of grasslands. NDVI may be used to determine the spatial distribution and the frequency distribution of herbage mass in grazed pastures, to georeference locations of warm season grass species in cool season pastures, and to evaluate the establishment of clovers in cool season pastures.  However, a basic understanding of current site characteristics (species and management) is needed in order to interpret data.