A combine harvester, comprising: a threshing system for threshing and separating crop material; a cleaning system for separating grain from chaff, the cleaning system being positioned to collect crop material falling from the threshing system; a plurality of threshing system sensors for detecting an amount of material passing from the threshing system to the cleaning system, at least two of the threshing system sensors being spaced apart along a longitudinal axis of the combine harvester; a plurality of cleaning system sensors for detecting an amount of material passing through the cleaning system, at least two of the cleaning system sensors being spaced apart along the longitudinal axis of the combine harvester; one or more computing devices configured to - receive data from the threshing system sensors and from the cleaning system sensors, and use the data to generate a graphical user interface including - in a first portion of the user interface, a graphical representation of an amount of material passing through the threshing system at multiple positions along a longitudinal direction of the combine harvester, and a graphical representation of an amount of material passing through the cleaning system at multiple positions along the longitudinal direction of the combine harvester, characterized in that at least two of the threshing system sensors are spaced apart along a lateral axis of the combine harvester; at least two of the cleaning system sensors are spaced apart along the lateral axis of the combine harvester; and in a second portion of the user interface, the one or more computing devices is configured to generate a graphical representation of an amount of material passing through the threshing system at a plurality of locations along a lateral axis of the combine harvester, and a graphical representation of an amount of material passing through the cleaning system at a plurality of locations along the lateral axis of the combine harvester. a threshing system for threshing and separating crop material; a cleaning system for separating grain from chaff, the cleaning system being positioned to collect crop material falling from the threshing system; a plurality of threshing system sensors for detecting an amount of material passing from the threshing system to the cleaning system, at least two of the threshing system sensors being spaced apart along a longitudinal axis of the combine harvester; a plurality of cleaning system sensors for detecting an amount of material passing through the cleaning system, at least two of the cleaning system sensors being spaced apart along the longitudinal axis of the combine harvester; one or more computing devices configured to - receive data from the threshing system sensors and from the cleaning system sensors, and use the data to generate a graphical user interface including - in a first portion of the user interface, a graphical representation of an amount of material passing through the threshing system at multiple positions along a longitudinal direction of the combine harvester, and a graphical representation of an amount of material passing through the cleaning system at multiple positions along the longitudinal direction of the combine harvester, at least two of the threshing system sensors are spaced apart along a lateral axis of the combine harvester; at least two of the cleaning system sensors are spaced apart along the lateral axis of the combine harvester; and in a second portion of the user interface, the one or more computing devices is configured to generate a graphical representation of an amount of material passing through the threshing system at a plurality of locations along a lateral axis of the combine harvester, and a graphical representation of an amount of material passing through the cleaning system at a plurality of locations along the lateral axis of the combine harvester.