Strategies for Improving Nutrient Use Efficiency in Corn and Small Grains.

World fertilizer nitrogen consumption will soon exceed 100,000,000 metric tons. Applying all N preplant is the most inefficient method of applying fertilizer, yet this method continues to be condoned in much of the Central Great Plains. Successful strategies to increase nitrogen use-efficiency include 1) preplant soil testing to determine soil-available ammonium and nitrate forms, 2) use of nitrogen rich strips applied preplant in cereal production fields to assist farmers in determining accurate mid-season fertilizer N rates, 3) use of NDVI sensors for mid-season prediction of yield potential, and N responsiveness when using N rich strips that ultimately lead to season specific fertilizer rates, 4) sensor based systems that look at specific portions of the plant where specific nutrient deficiencies are encountered, and 5) by-plant fertilization systems capable of applying prescribed rates at the 15 cm scale. Nutrient rich strips applied preplant in each field are the most affordable, practical and useful technology available today for improving use efficiency that varies year to year and field to field.