corn, heat units, maturity stages, calendar days
The number of calendar days and growing degree days needed for corn to mature form one growth stage to another are indicated in Table 1 (next page). Use caution when applying table values to specific growing conditions since they are approximations and may vary slightly according to environment and corn hybrid.
Hall, Robert, "Number of Calendar Days and GDDs Needed by Corn to Mature at Given Growth Stages" (1995). SDSU Extension Extra Archives. 310.