Abstract: A harvester which has a global-positioning system is used to harvest crops. Fields to be harvested are divided into individual field areas for crop quality assessment selected by the farmer. Values representing the location of the selected individual field areas or crop management areas are loaded into storage on a computer or recorded. The harvester also includes a dispenser of crop markers. Each crop marker has a unique identifier when compared to the other crop markers used during the harvest. The global-positioning system determines actual field location during the harvest and when an actual field location is close or matches one of the selected field locations, a trigger signal is sent to the dispenser and a crop marker is inserted into the harvested crop stream. A table of selected field locations and the crop markers inserted into the crop stream from that field location is stored. Later on in processing, the crop marker is detected and a sample of the crop is taken from around the crop marker.