Cereal production that now sustains a world population of more than 6.5 billion has tripled
during the past 40 yr, concurrent with an increase from 12 to 104 Tg yr− 1 of synthetic N …

Core Ideas Nitrogen recommendations for individual corn fields are less accurate than
desired. Nitrogen recommendations need improvement for economic and environmental …

Intensive use of N fertilizers in modern agriculture is motivated by the economic value of
high grain yields and is generally perceived to sequester soil organic C by increasing the …

Determining which corn (Zea mays L.) N fertilizer rate recommendation tools best predict
crop N need would be valuable for maximizing profits and minimizing environmental …

Nitrogen recommendations based on corn (Zea mays L.) yield goal can overestimate N
needs if yield expectations are not realistic, and yield goal‐based N recommendations may …

The concentration of NO− 3 in the lower portion of cornstalks at physiological maturity has
been proposed as the basis for evaluating the N status of corn (Zea mays L.). Here we refine …

Improved N management programs for fertilizers and manures are needed in the Atlantic
Coastal Plain because of concerns about agriculture's role in groundwater contamination …

Agriculture is among the principal contributors of nonpoint source pollution, a major cause of
impaired water quality (Puckett). The amount of agricultural pollution depends in part on …

Improving corn (Zea mays L.) nitrogen (N) rate fertilizer recommendation tools can improve
farmers' profits and mitigate N pollution. Numerous approaches have been tested to improve …

Agriculture's impacts on water quality have been the focus of basic and applied research in
Delaware for more than 25 years. Research has examined nutrient cycling in soils, nutrient …