PSNT, ISNT, SPAD, etc….. What’s it All Mean?
With higher fertilizers prices becoming the norm, scientists and producers alike are looking for alternative (hopefully better) methods of making nitrogen fertilizer rate decisions. Currently there are a number of methodologies promoted, but sometimes the scientific underpinning is lost in the discussion. The objective of this presentation is to provide information on how the methodologies are supposed to be utilized, where they have application, and where they have shortcomings. Various technologies will be discussed including the presidedress nitrate soil test (PSNT), the Illinois soil nitrogen test (ISNT), the use of SPAD meters, and the use of remote sensing.
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Robert Mullen Assistant Professor/Extension Soil Fertility Specialist
Ohio State University/OARDC-SENR
Dr. Robert Mullen is an Assistant Professor of Soil Fertility and Nutrient Management at Ohio State University/Ohio Agricultural Research and Development Center (OARDC). Dr. Mullen received his B.S. in Ag Business at Cameron University in Lawton, Oklahoma in 1998. Dr. Mullen earned his M.S. in Plant and Soil Science and Ph.D. in Soil Science from Oklahoma State University in 2001 and 2003, respectively. Prior to completing his Ph.D. program, Dr. Mullen was employed as an agronomist by NTech Industries Inc. where he worked with sensor-based, site-specific technology across the Great Plains and Western Corn Belt. He joined the faculty at Ohio State University in April of 2004. His research program focuses on soil fertility issues for production agriculture, and the use of sensors measurements to direct nitrogen application for corn production. Dr. Mullen also conducts research on alternative cropping systems, manure management, and economic methods to decrease environmental contamination of nutrient sources.