series of global positioning satellites 38 in orbit about the earth remote computer 32 requests pre existing field data from various established databases 36 this data can include for example nrcs soil surveys or other soil maps crop yield digital elevation models satellite images air photos orthorectified air photos geology surveys soil and water test information land use records and history and field and property boundaries in some cases the field boundary 28 is initially determined on site by initially driving test vehicle 16 around the area to be mapped while recording boundary marks with the gps system the available data is then compiled using software contained either on test vehicle 16 field support vehicle 30 or from remote computer 32 to form an integrated database reflecting the known information with respect to field 26 in some cases more than one test vehicle 16 is deployed in a field at a given time to promote testing and sampling efficiency the test vehicles may all perform the same types of tasks or may each be equipped to perform a specialized task with all preferably coordinated from a single remote vehicle 30 or computer 32 while the test vehicle may be a wheeled or tracked mobile platform in some cases it comprises a set of instrumentation and sensors carried about in a backpack or pushed about on a cart or sled by a test operator referring to fig4 a significant part of an efficient process of refining or improving the soil map of field 26 is collecting and integrating the pre existing data from various accessible sources because such data is represented in.