Source: DuPont Pioneer
Monitoring nitrogen (N) at key points during the growing season is critical for plant growth and grain fill. A wet spring also could contribute to concerns about N being available to the plant due to leaching or denitrification.
Growers should be evaluating how much N remains in the soil and if it will be enough to meet crop needs. A quick response to N-deficiency stress is often required to minimize yield loss.
Soil tests are one way to gauge nitrogen levels. Optical sensors can also be mounted on fertilizer application equipment, enabling on-the-go N sensing, rate calculation and application all at once. Aerial imagery and chlorophyll meters are also good tools to use.
If N is found to be lacking in the plants and soil, growers have several decisions to make, including:
- the type of N to apply
- application method
- volume of N needed
- need for a nitrification inhibitor
Several research studies show that rescue N applications are effective at recovering yield — as late as three weeks after pollination.
Here are a few resources on N management: