Determining the type of fertilizer, and the rate needed should depend on soil test recommendations. “Soil testing is proven scientific technology and works extremely well. With current fertilizer prices, soil testing is essential. If fertilizer is 50 cents a pound, we need to test every year and use those dollars efficiently.”

McFarland said accurate soil tests account for nutrient carryover. “Nutrients occur naturally in the soil,” he said. “Poor crop years may also leave residual fertilizer for a subsequent crop.

“Measure the amount in the soil and evaluate the needs of the crop and yield goals. Then get a sound recommendation.”

He said waiting until a deficiency shows up before altering fertilization practices hurts production. “By the time you see a deficiency, the crop is already damaged.”