Geographic information system (GIS)

• General-purpose GIS packages, such as ARCVIEW, IDRISI, and SURFER, provide many functions, some of which offer little value to PA applications.
• Most of these packages are expensive and require computer platforms that are not usually possessed by farmers.
• To address the urgent need for PA applications at the field level, many commercial GIS packages, such as the software packages introduced by AGRIS Corporation, Farm Works TM, Agri-Logic, Inc., John Deere Precision Farming Group, Case Corporation, Rockwell International, and RDI Technologies, Inc., have been developed (Ess et al., 1997)
• Some systems directly interact with DGPS devices or yield sensors to acquire location and yield data in real time.
• Runquist et al. (2001) developed a field-level GIS (FIS) containing analytical functions for spatial data analysis in PA research.