Field Phenotyping is the way to go for many. Without doubt UAV’s are the mainstream solution for many uses.
There are however use-cases where the UAV’s cannot deliver the required sensor payload or resolution. For these cases a Ground based / Rover vehicle could be a solution. Ground based vehicles often do not have payload restrictions and can deliver much higher resolutions due to the closer proximity.
Often Field Phenotyping rovers are used for the exploration and development of new methods that at a later stage can be simplified and implemented into the UAV platforms.