GDD is a method to define the accumulated temperature needed for hybrids to reach maturity
GDD’s are calculated by adding the high temperature for the day and the low temperature for the day, dividing by 2 and subtracting 50.
86 degrees is the maximum high and 50 degrees is the minimum low. In other words, if the maximum daily temperature is 90 degrees, 86 is used in the calculation. If the minimum daily low temperature is 47 degrees, 50 is used in the calculation.
GDD’s for corn are typically calculated from the date of planting.
Corn normally requires about 110 GDD’s for corn to emerge.