ACS CCN1 case studies
ACS CCN1 · Put your knowledge to work in context.
The ACS Certified Crop Nutritionist (CCN1) is a professional credential for agronomists, crop consultants, fertilizer and nutrient-management advisers, extension staff, and farm managers who make nutrient recommendations. It signals that the holder can reason from soil and tissue data to a defensible nutrient plan that balances crop yield, cost, and environmental risk. The exam is multiple choice and spans eight domains: soil fertility and plant nutrition fundamentals; nutrient sources, fertilizer materials, and amendments; soil testing and tissue analysis interpretation; nutrient management planning and application methods; environmental stewardship and nutrient loss prevention; crop-specific nutrition and yield quality; regulatory, safety, and ethics; and record keeping, economics, and decision support tools. The weighting is roughly even across the technical domains, with smaller shares for stewardship, crops, regulation, and economics, so candidates should expect calculation items (fertilizer grades, application rates, nutrient balance) alongside concept and interpretation questions. The ACS CCN1 case studies are 5 cases and about 1,968 words.
1Split Nitrogen Timing in a Wet Spring for Irrigated Corn
A central Nebraska producer has 160 acres of continuous corn following soybean, expected yield 240 bu/ac. In late March he applied 120 lb N/ac as anhydrous ammonia (82-0-0) pre-plant.
508 words, about 3 min2Phosphorus and Manure on a High-P Soil Field
A dairy operation in Wisconsin has a 40-acre corn field that has received manure for 15 years. Soil test P (Bray P1) is 95 ppm, well above the agronomic critical level (about 30 ppm for corn).
409 words, about 2 min3Tissue Analysis Interpretation in a Bearing Apple Orchard
A New York apple grower has a bearing block of Honeycrisp on M.9 rootstock. Leaf samples were collected at 60-90 days after bloom from mid-shoot leaves.
402 words, about 2 min4Variable-Rate Nitrogen with a Drone Imagery Decision Tool
A 500-acre corn and soybean farm in Iowa uses a variable-rate nitrogen prescription based on drone NDVI imagery collected at V8. The imagery shows a 40-acre low-NDVI zone in a field that received 150 lb N/ac pre-plant.
343 words, about 2 min5Anhydrous Ammonia Safety and Regulatory Compliance
A certified applicator plans to apply anhydrous ammonia (82-0-0) to 80 acres at 140 lb N/ac. The nurse tank is transported 30 miles on a public highway.
306 words, about 2 min