Drought-Stressed Grain Harvest

Crop Condition

  • Depleted sugars in the stalk and collapsed cells contribute to early death and poor standability.
  • Collapsed ear shanks may cause dropped ears.
  • Stalk rot and ear rot pathogens can invade and grow rapidly if moisture returns.
  • Insect infestation in field or storage may increase infection by stalk or ear rots and affect ability to harvest or store the crop.
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Harvest in a Timely Manner

  • Stressed crops may deteriorate rapidly due to standability or grain quality issues.
    • If wet conditions develop, crop condition will worsen even more quickly.
  • Assess crop condition early and prioritize field harvest order accordingly.
  • Drydown will be rapid. Moistures below 15% represent loss of saleable product.

Use Care When Setting Combine

  • Adjust speed to keep the machine full and adjust gathering chains accordingly.
  • Small, rubbery cobs will be difficult to thresh. Adjust concave, cylinder, fan speed and stripper plate settings accordingly, beginning with the manufacturer’s suggested settings.
  • Decrease the concave clearance first, then adjust cylinder speed, beginning lower than normal.
  • Adjust sieves to retain a smaller grain size.
  • Reduce the air carefully to remove lightweight materials but not the grain.
  • Check frequently for changes in the crop or equipment that require readjustment.
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Handle Grain Carefully

  • Stress cracks / broken kernels harbor high levels of fungi and easily develop storage diseases.
  • Use a rotary screen, perforated auger housing or other screen to remove fines and broken kernels before storage.
  • After filling, extract and redistribute grain from the bin center cone to remove the accumulated fines that restrict air flow.
  • Monitor grain temperature and moisture regularly to detect “hot spots” of moisture or fungal activity early.
  • Follow other recommended practices for long-term storage at Maintaining Corn Grain Quality Through Harvest and Drying.
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Grain Sale and Delivery

  • Find market outlets early.
  • Ability to take drought-stressed grain with inherent quality problems may be a factor for some buyers.
    • Limits for broken or moldy kernels and test weight will differ, depending on export or domestic destinations.
    • This will affect the ability to purchase or mix grain in some channels.
  • Test grain samples and determine suitability for different buyers including local livestock or ethanol production as appropriate.

Reassess Tillage and Fertility Practices

  • Overall stover levels will be lower, reducing the amount of tillage needed to manage it.
    • Less tillage will save fuel and time while increasing erosion control.
  • Lower fungal disease incidence in dry weather means lower inoculum levels on exposed residue for next year.
  • Low grain yields mean reduced need for nutrient replacement; consider three-year replacement cycle rather than two-year cycle.
  • If harvest removed silage or stover, increased removal of P and K is likely.
  • Dry summer soils will reduce nitrogen loss by leaching or denitrification. Consider testing for nitrogen before application if the field is going to corn next year.
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Assess Crop Rotations

  • Consider possible residual nitrogen as a factor if going back to corn.
  • Future weed seed supply in the soil will be ample where herbicides had difficulty controlling stressed weeds in dry soils.
  • Herbicides fail to break down in dry soils, which could affect following crops.
    • Depends on chemical used and method and timing of application
    • Some crops and varieties/hybrids are more sensitive to specific chemistries
    • Ask for and adhere to the manufacturer’s recommendations for following crops when there are risks of crop response
  • Drought was widespread but conditions varied and different regions will have different problems, many of which may not be known until next spring.
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Extreme Widespread Drought Occurs Infrequently

  • Be cautious before making drastic changes in management based on one year’s experience.

  • Use hybrids that have proven successful over a period of years.

  • Significant reductions in planting rates could limit yield potential in a more normal year.

  • No year is average. Flooding is just as likely as a drought next year.