University of Minnesota Extension
Menu Menu

Extension > Minnesota Crop News > Archives > September 2004 Archives

September 2004 Archives

Mark Seeley
Extension Climatologist

As we have been hearing the cold growing season has exposed this year's corn and soybean crops to higher risk of frost damage and more importantly the likelihood of not maturing and being at high moisture content for harvest. Some have referred to their experiences with other similar growing seasons. These are climatically hard to find and not very many in number.

Please find below the ten coldest growing seasons at the University of Minnesota Southern Research and Outreach Center in Waseca, MN. This ranking is based on Growing Degree Days (GDD base 50/86 F) for the May 1 to August 30 period. Also listed are the following September GDD values and the first frost date of the designated year. The parenthetical values are the long term averages.

Year 5/1-8/30 GDD


Sept GDD

Frost Date

1915 1687 372 9/10
1917 1697 301 9/21
2004* 1775 ? ?
1967 1776 344 9/24
1924 1794 293 9/30
1945 1817 377 9/28
1927 1834 486 9/20
1992 1860 352 9/29
1979 1894 399 10/7
1968 1913 327 10/4
1966 1923 374 10/1

Please note that in almost all cases the combination of September GDD and later frost date did not materialize to make up for the slow crop development associated with fewer seasonal GDD accumulation. A warm, early September in 1927 produced above normal GDD values, but an early' frost occurred on the 20th. A warm September and later than normal frost in 1979 was offset by an extremely late plant date that year that did not allow the crops to reach maturation.

The corn crop - frost and maturity

| Leave a comment

D. R. Hicks
Dept. of Agronomy and Plant Genetics, University of Minnesota

Many cornfields over Minnesota lost some leaves to the frost of Saturday morning August 21. But, except for low areas in some fields, there remains green leaves that can continue to add grain yield. This note gives an update of corn development as the crop moves, albeit slowly, toward maturity. And since some of the crop is not likely to reach normal maturity, this newsletter also gives information regarding the effect of frost before maturity on corn grain yield, dry down, and grain quality.

Corn test weight changes during drying

| Leave a comment

Dale R. Hicks
Department of Agronomy and Plant Genetics, University of Minnesota

Some of this year's corn crop will not reach normal maturity before the next killing freeze. As a result, maximum yield potential and normal test weights will not occur. Test weights in the low 50's(lb/bu) may be common in some areas the state, especially in the northern half of MN. Test weight can increase with artificial drying if the drying temperature is maintained below 180°F.

  • © 2014 Regents of the University of Minnesota. All rights reserved.
  • The University of Minnesota is an equal opportunity educator and employer. Privacy