John Sawyer
Position
- Retired Nitrogen Soil Fertility Specialist and Professor
Dr. John Sawyer is a former professor of agronomy and a former extension specialist in soil fertility and nutrient management at Iowa State University. He earned a Ph.D. in Agronomy from University of Illinois. His research includes fertilizer and limestone needs of agronomic crops, manure nutrient utilization, site-specific systems, and impact of soil management and nutrient application on water quality. Dr. Sawyer is an ARCPACS Certified Professional Agronomist, ARCPACS Certified Professional Soil Scientist, and Certified Crop Adviser.