Pictures of severely drought-stressed corn have been common in the media in recent weeks, but this silking double-eared corn on nine-foot stalks in a field on the Paul Meyers farm in southern Calumet County is an exception. This was true although the rains which have moved through Wisconsin starting in the third week of July have bypassed this location. Some other corn in the immediate area is showing the effects of drought. Photo By Ray Mueller
July 18 rains might have saved some southern Wisconsin corn
"Having to make the best of a bad situation" is a phrase that University of Wisconsin Extension Service corn agronomist Joe Lauer used in a July 7 article that he admitted he "dreaded writing."
What Lauer was writing about was the approaching pollination period for much of the corn crop in southern Wisconsin when the weather and growing conditions were not conducive to good pollination.
He continued to post updates every one or two days advising corn growers in an area covering at least the four southern tiers of Wisconsin counties on how to salvage some value from corn with poor pollination.
That continued until a significant rainfall (one to three inches in many instances) arrived in much of the affected area on July 18. Smaller amounts of rain fell over part of that territory on several following days.
In his July 19 update, Lauer observed that the rain "arrived a little late for some fields" but he was confident that the replenishment of soil moisture would "relieve stress long enough for some fields to complete pollination."
When asked whether the July 19 and subsequent rains was enough to save this year's corn crop, Lauer looked to history.
He noted that somewhat similar conditions prevailed in 2005 until rain arrived on July 19, followed by more rains during the latter half of the corn growing season and some record yields were set.
Lauer credited the role of transgenic traits as being a probably factor in 2005 compared to other drought years such as 1976, 1988, and 1989.
While those traits reduce plant stresses such as those posed by insects, he emphasized that water is essential (20-24 inches of rain during the growing season) for producing an acceptable corn crop.
To questions about the effects on this year's corn yields, Lauer indicated on July 17 that it was "too early to predict the success of pollination" but acknowledged "it is not looking good."
When the days for possible pollination occur depend on a combination of the planting date, growing conditions, and the rated maturity of the corn hybrid.
Once the period for pollination has passed, it is possible to find out whether it occurred with an "ear-shake test" and to make subsequent management decisions based on whether the corn will have a significant amount of grain or not, Lauer indicated.
Details about conducting that test are available on a video that can be accessed through the corn.agronomy.wisc.edu/Season Web site or Lauer's wisccorn.blogspot.com
If the corn proves to be barren or nearly so, one option is to harvest it fairly soon for silage and plant another crop as an emergency forage if the grower would need it for livestock feed or even as a cash crop, Lauer pointed out.
Deciding on an emergency forage route would ride on how and when the crop would be used, what level of forage quality is needed, and the forage seed availability and cost, he stated.
Arriving at a fair and equitable price for corn silage that doesn't have much grain content and that would be harvested six to eight weeks before normal will be difficult because of the combination of dynamic and biologically variable factors, Lauer observed.
He listed such factors as production and harvesting costs, moisture content of the silage, grain price (not very significant if there's little or no grain), costs of handling, hauling, and storing forage, fertility and organic matter value of corn stover, and supply and demand in the area.
An accompanying risk with poor pollination is the possibility of nitrate poisoning, Lauer points out.
He explained that this would happen in large part because of the concentration of nitrates that occurs when the volume of dry matter is only about one-half of that of normal corn.
If nothing else, and although "a season like 2012 is rare and extreme," Lauer tells corn growers that "it will likely happen again."
He urges them to take some time to evaluate what happened this year and how they could possibly cope better if it happens again.
As one of several scheduled followups on the 2012 growing conditions and their effects, Lauer and Extension Service entomologist Eileen Cullen will be speaking at a meeting sponsored by the Dodge and Fond du Lac Corn Growers association on Tuesday, July 31.
The meeting will start at 6 p.m. in a field on the Ed Montsma farm along Highway 151 between County TC and Lamartine in Fond du Lac County and then move to the town hall for brats and beverages.