| Precision farming is an emerging technology that enables the producer to measure, monitor and manage factors that influence yield variability providing farmers with a higher level of management information and control. This study seeks to develop an increased understanding of precision farming techniques and to evaluate whether they can be applied to improve economic efficiency of agricultural production management. Variable N management is expected to reduce the number of areas in a field that are either under- or over-applied. Field-specific agronomic data were used to conduct an economic comparison of variable nitrogen (N) management to uniform N application methods.;Estimation of a quadratic site-specific production function for each site in 1994 and 1995, was the basis for evaluating the impact of field conditions on yield variability. Results and conclusions obtained from this analysis are conditional on the production functions estimated. Variables significant in determining corn yield at these sites were N available as a function of N applied and nitrate present in the soil, over- and under-application of N, elevation, relative change in elevation, organic matter, and the sandy texture of the soil. In general, N had a positive impact on yield while over- and under- application of N with respect to the prescribed N recommendation, had a negative impact on yield. Less total N fertilizer was used with variable-rate than uniform N management. Additional returns to variable N over uniform N management were determined and compared against the estimated additional costs of variable-rate N management. The net return to variable N management was positive at least once for each field during the two years studied. The results indicated potential for profitable use of variable-rate N management. Variable-rate technology may require higher application and management costs, but the overall return measured through yields, fertilizer inputs, and environmental implications of fertilizer use will favor variable-rate N fertilization. |
