Today marks the weekly posting of accumulated corn and soybean developmental degree days (base 50º F) for the nine Iowa crop reporting districts. Because data in previous years has been posted for a growing season that starts May 1, we will again post with the May 1 start date.
Superimposed on the map below is the accumulated degree days gained for three different periods in April 2005: April 1 through May 1, April 10 through May 1, and April 20 through May 1. Note that the longer time periods include the later, shorter ones; by example in northwest Iowa all of April was 44 degree days above normal, but that includes the cold last 10 days that took away 57 degrees, so actually the first 20 days of April was 101 [44 + 57] degree days above normal.
For farmers that planted corn or soybean in April, this data can help adjust the data posted throughout the rest of crop year 2005.
As of this morning (May 2) approximately 70-75 percent of corn was planted in Iowa, so once we survive the current cold spell, May growth should come on like gangbusters.
This article originally appeared on page 69 of the IC-494 (8) -- May 2, 2005 issue.