Developing and Using Nonlinear Response Functions: A Potential Method for Nutrient Recommendations.

To maximize profitability it is necessary to plant the most profitable population every place in the field.  Given the relatively high cost of corn seed ($4/per 1000 seeds), corn will be used as an example of a crop for which this is particularly true.  Perhaps the most significant Precision Farming adoption barrier is the lack of availability of  “good” application recommendation algorithms.  Within a geographical area, for a relatively narrow field yield potential range (150 to 170 bu/acre), and for a specific genetic material, it is possible to develop an acceptably consistent yield response curve (yield =f(plant population).  Given this yield response curve, the cost of seed, and the value of the corn, the optimum population rate is determined by solving the equation.  This same process can be accomplished for multiple different yield potential ranges. Once the optimum population has been determined for multiple ranges an equation for, optimum planting population =f(yield potential) is written.  Across a field, site specific field yield potential are determined using multiple years of yield monitor data.  A optimum plant population map based upon the long term yield map and the developed optimum planting population equation will then be developed.