When growers face suboptimal crop yields due to drought, a common question is how much fertilizer will be required for the next growing season.

Consider crop removal:

Soil nutrient removal by corn and soybeans.

Nutrient Removal

Less grain and stover removal means less nutrient removal.

Nutrients removed at various corn yields:

Nutrients removed at various corn yields.

Nutrients removed at various soybean yields:

 drought-affects-nutrients-soybean-yields

Soil Sampling in a Very Dry Fall

Soil sampling
  • Concern: Clay minerals shrink - hold potassium (K) ions
  • Result: Inaccurately low K soil test results
  • Action: Wait for adequate soil moisture before sampling

Nitrogen (N) Remaining in Corn Fields

  • Poor plant uptake of N due to dry weather
  • Nitrogen in nitrate form in the soil
  • Lack of moisture has prevented leaching or denitrification
  • Environmental loss of N has been minimal

Trap Crops

  • Wheat and cereal rye are best crops to prevent nitrogen loss
  • Nitrogen will not be available to the subsequent crop due to immobilization of N in the residue
  • When growing wheat for harvest, fall N can be eliminated while spring N may be reduced
  • Using trap crops improves organic matter and soil tilth, while improving water quality

Conclusions

  • Applying maintenance rates or no fertilizer may be acceptable depending on yield and previous soil test results
  • Avoid soil sampling until moisture levels return to normal
  • Wheat may be a good crop to take advantage of leftover nitrogen. Watch for head scab when planting wheat after corn.


The foregoing is provided for informational use only. Please contact your Pioneer sales professional for information and suggestions specific to your operation. Product performance is variable and depends on many factors such as moisture and heat stress, soil type, management practices and environmental stress as well as disease and pest pressures. Individual results may vary. Pioneer® brand products are provided subject to the terms and conditions of purchase which are part of the labeling and purchase documents.