Zones can be sensibly created based on the farmers knowledge:
Results will show values in each zone which is mapped clearly and colour coded for ease of understanding. Future applications can be targeted easier managed more effectively.
Zones would normally be sampled simultaneously with grid sampling for greater efficiency as all sample points are logged via G.P.S for a repeatable service.
PCN, FLN, Black Dot, Powdery Scab, Club Root amongst other tests available would be sampled in designated zones or 1 per field to remain cost effective.