Is it economically feasible to harvest by management zone?

The economics of harvesting wheat based on input management zones in the northern wheatbelt of Western Australia was studied using a simulated field of regular dimensions with varying zone sizes and layouts. Fertilizer application rates and crop yield and quality data from field trials of input management were used to estimate the gross crop revenue and harvesting costs from the different field layouts and zone combinations. As a general observation there was no consistency in the results; harvesting by zone generated more gross income in some combinations of field layout and yield quantity scenarios, but not in others. However, there were key factors in determining whether it was profitable to harvest by zone. These were prior knowledge of the potential yield and quality characteristics of grain from each zone in a field, and the layout of zones within a field.