Dr. John Sawyer is a professor of agronomy and extension specialist in soil fertility and nutrient management at Iowa State University. His extension program involves soil fertility management, efficient crop nutrient utilization, and environmentally sound fertilizer and manure systems. Dr. Sawyer's educational efforts focus on helping producers, agronomists, and industry leaders better understand soil-nutrient interactions with water quality. 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.