In better-watered areas of Illinois where the corn crop is well established, the return of warm temperatures has caused very rapid growth. Corn planted in central Illinois in mid-March and not damaged by frost has accumulated about 900 growing degree days (GDD) by now and, thus, has reached stage V9 or V10, the point at which stem elongation accelerates. Such fields will likely show tassels by mid-June. Corn planted in early April has accumulated about 650 GDD and is at V7. Corn planted in mid-April is at V5, having accumulated approximately 520 GDD.