Purdue corn specialist: Cool weather's effect on crop could differ from 2009
July 25, 2014
WEST LAFAYETTE, Ind. - The next two months will determine whether the Indiana corn crop produces high yields as expected or is significantly damaged by any unforeseen, drastic changes in weather and diseases, Purdue Extension corn specialist Bob Nielsen says.
This growing season at first glance appears similar to 2009, when planting was delayed because of cold weather and the growing season was cool through this time in July, Nielsen notes in an article Thursday (July 24) his Corny News Network. The cool weather that year continued through much of the summer and into early fall, further delaying the crop's maturing.
"Coupled with poor conditions for grain drying in the field prior to harvest plus the development of ear rots and mycotoxins, grain harvest was pretty miserable for many growers in 2009," Nielsen said. Nevertheless, he added, estimated statewide grain yield in Indiana set a state record at 171 bushels per acre, exceeded only by last year's 177.
"One needs to be cautious making comparisons with the 2009 growing season, especially with regard to the unpleasant harvesting experience of 2009," he said.
There are several differences between this year and 2009, Nielsen's research shows:
* While the onset of planting was delayed this year, most of the crop was planted ahead of the five-year average pace, compared with the overwhelming late planting of 2009.
* While cool temperatures to date have slowed the crop's progress, the statewide pace of silking as of July 20 remains slightly ahead of the five-year average.
* Stand establishment (plant population and initial uniformity) appears to have been excellent throughout the state, except for fields or areas within fields that sustained damage from excessive rainfall earlier in the season.
* The National Weather Service's outlooks for August through September for Indiana suggest normal temperatures (not excessively hot or cool) and normal rainfall (not excessively wet or dry). Nielsen says that would bode well for the important grain filling period (kernel weight) and for minimizing risk of further delay in the crop's progress as it moves toward maturity.
* Foliar disease levels to date remain moderate in most fields.
Many of the record-high years for corn grain yield in Indiana have been those with moderate, if not cool, temperatures during the growing season, Nielsen said.
Potential bad news for farmers, he said, depends on the weather; diseases, including ear rots; and the adequacy of soil nitrogen for finishing the crop without any undue photosynthetic stress during the grain filling period.
"The question lingers about the 2014 growing season and its cool temperatures to date," Nieslen said. "The honest answer to that question is time will tell because the next 60 days will decide whether this crop finishes as strong as much of it looks today or falters in response to yet unknown weather extremes and/or diseases."
Seventy-six percent of Indiana's corn crop was rated in good or excellent condition as of the week ending July 20, compared with 78 percent at the same time last year, according to the U.S. Department of Agriculture's National Agricultural Statistics Service.
The State Climate Office, based at Purdue University, expects temperatures the week of July 28 in Indiana in the mid-70s to low 80s for highs and lows in the mid-50s to 60. That would be below the normal highs of mid-80s and lows in the mid-60s.
This July is heading toward surpassing 2009 as the coldest July on record since 1895.
Nielsen's full report is available at http://www.agry.purdue.edu/ext/corn/news/articles.14/CoolTemps-0724.html
Writer: Keith Robinson, 765-494-2722, firstname.lastname@example.org
Source: Bob Nielsen, 765-494-4802, email@example.com