Accumulated Growing Degree Days

A precise method of describing the maturity of a corn hybrid is to define the accumulated temperature needed for that hybrid to reach maturity. Research has shown that the development of the corn plant follows very closely the accumulation of average daily temperatures during the plant's life. This accumulation is calculated as "growing degree days" (GDD). The GDD concept has been very useful in knowing how the crop will respond to temperatures and in helping to fit hybrids into situations where expected GDD accumulations are known from weather records. The following form will calculate the GDD for one day using 50 as the minimum temperature and 86 as the maximum temperature. If you keep calculating for more than one day a running total will be kept and the expected stage of development will be given. Also, at the bottom of the form is a table to look up the expected stage of development for a given accumulated GDD.

Temperatures for the day Fahrenheit:
(between 50 and 86 F)
Low: High:
GDD for the day: Total Days: GDD running total:
Expected stage of development:

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