As of May 12, 15 percent of Iowa’s corn was planted (USDA-NASS). This is a slower pace than what Iowan’s experienced even in the flood year, 1993, when 20 percent was planted at this time in May. The 8 percent planted before May 5 was subjected to dramatic soil temperature changes as well as up to a foot of snow in parts of Iowa. Many Integrated Crop Management News articles, blogs, Twitter posts, and other media document spring 2013 conditions and concerns.
Iowa State University
Elmore, Roger W. and Taylor, S. Elwynn, "Analog Years for Weather Forecasting and Correlating Corn Planting Dates with Yield in Iowa" (2013). Integrated Crop Management News. 82.
Figure 1. Iowa Average Accumulated Growing Degree Days (GDD), Precipitation, and Stress Degree Days (SDD) for Spring 1947, 1995 and 2013.
20130515-ElmoreR-AnalogYearsWeather-Figure2.pdf (298 kB)
Figure 2. Iowa Average Accumulated Growing Degree Days (GDD), Precipitation, and Stress Degree Days (SDD) for the 1947, 1995 and 2012 Growing Seasons.
20130515-ElmoreR-AnalogYearsWeather-Figure3.pdf (183 kB)
Figure 3. Corn yield United States. and Iowa, 1866-2012.
20130515-ElmoreR-AnalogYearsWeather-Figure4.pdf (172 kB)
Figure 4. Percent of Iowa's corn planted at different dates and years. 2004 and 2009 yields were well-above trend line. Record breaking planting progress occurred in 2010.
The Iowa State University Digital Repository provides access to Integrated Crop Management News for historical purposes only. Users are hereby notified that the content may be inaccurate, out of date, incomplete and/or may not meet the needs and requirements of the user. Users should make their own assessment of the information and whether it is suitable for their intended purpose. For current information on integrated crop management from Iowa State University Extension and Outreach, please visit https://crops.extension.iastate.edu/.