Which of the following factors can influence increased nitrogen loss?

• A. All of the above
• B. Not accounting for nitrogen from manure applications
• C. Weather conditions resulting in reduced yield
• D. Placement of nitrogen during application

Answer: (D)

Placement of nitrogen during application matters most because it directly controls how much of the applied N stays in the root zone and how much is exposed to loss pathways. When nitrogen is placed in or near the root zone and properly incorporated or banded, it is kept where crops can take it up and is protected from rapid losses. If it is left on the surface, broadcast, or placed too far from roots, it becomes more vulnerable to volatilization as ammonia, runoff with rain, and deep leaching, all of which increase nitrogen losses. While manure accounting and weather can influence overall nitrogen management and crop response, the way nitrogen is positioned during application is the primary factor that determines the immediate potential for loss.