Submitted to: Intnl Conference On Geospatial Information In Agriculture And Forestry
Publication Type: Proceedings
Publication Acceptance Date: November 7, 2001
Publication Date: N/A
Within field soil variation and placement of strips to evaluate plant nitrogen status poses a problem. Field level research in six producer fields in Iowa addressed quantification of N sufficiency relative to application rates and resulting grain yield. Fields were stratified, using soil survey and remotely sensed bare soil imagery, to evaluate zonal management potential, and striped with nitrogen treatments that incorporated minimal N sufficiency. Soil nitrate-N, ear leaf nitrogen concentration, leaf chlorophyll, hand harvest yield, and high spatial resolution aircraft multispectral data were collected from statistically located plots within each strip. Strip yields were determined by yield monitor and weigh wagon. Statistical and quantitative analysis evaluated the relationship between N application rates and plant N status for plot and strip measurements. Spatial arrangement of nitrogen strips within fields may not be as critical as previously thought, however, sample size for soil and plant observations emerged as a critical parameter.