Seeking a pot of gold-Corn producers concerned about continuing drought
By Jennifer Carrico
The drought of 2012 affected nearly every farmer across the Corn Belt and it continues to linger, making farmers wonder if the 2013 growing season will have a pot of gold at its end.
"Right now our subsoil is very dry," said Lynnville, Iowa, farmer Roger Zylstra. "I have lived on or near this farm my entire 61 years and this is the driest I've ever witnessed."
He said the topsoil moisture is not in terrible shape right now, with moisture being seen about 18 inches down on his farm in east central Iowa. But he stressed the need for timely rain throughout the growing season to get the most out of this year's crop.
Iowa State University Extension Climatologist Elwynn Taylor said the drought of 2012 was the continuation of a weather pattern that started in 2010, moving from the east and south, up into the upper Midwest.
"The 2012 event ended a several-year drought in the northwest United States and ended a six-year continuous string of above-trend U.S. corn yields," he said.
A moisture deficit in the subsoil increases the risk of crop yields being below trend and prevents the recovery of river, pond and well water to normal levels, according to Taylor.
Zlystra said the river and creek levels in his area, which are a good indication of moisture levels, are the lowest they have been in many years.
Taylor said historically, the severely deficit precipitation years similar to 2012 do not recover to normal annual precipitation in one year.
"An additional year of significant moisture stress is considered to be not unlikely, and a fourth consecutive year of below-trend U.S. corn yield a distinct possibility," he added.
Iowa State University Agronomy Professor Mahdi Al-Kaisi said the combination of poor water availability and high temperatures resulted in significant stress during critical phases of corn and soybean development.
"These stress factors lead to management challenges with insects, diseases and reduced nutrient availability and uptake by plants," he said.
"The drought triggered soil changes, particularly in conventional tillage systems, such as increased fracturing, crusting and deterioration of soil structure and aggregation."
These changes in the soil structure can cause problems with the soil, water, and plant relationships and the root system development, which in turn affects yields.
Zlystra uses no-till practices on his farm in hopes of conserving as much moisture as possible and providing a healthy seed bed environment. Hog manure from his hog finishing operation is injected on the ground in the fall for fertilizer. Last year he started using pop-up fertilizer when he plants the corn and will use it again this year.
"The important thing this year, just like every other year, is that we need to monitor what is going in our fields and when a problem arises, we need to deal with it immediately," he said. "Especially with all the challenges we had last year."
While farmers don't manage their farms for what might happen, they do have to change some management practices throughout the growing season and in following years.
Corn nitrogen fertilization ranges necessary to provide optimum yield are typically lower in years with below-normal rainfall. Al-Kaisi said the effects of dry conditions should be considered in decisions for nitrogen application rates in 2013.
The current U.S. Drought Monitor map shows a large portion of the area where corn is grown to be experiencing drought conditions, ranging from moderate to exceptional.
Al-Kaisi said good soil management practices can improve soil's water storage efficiency and availability for crop use and decreasing drought effects.
Proper soil management can improve soil quality by improving soil aggregation, increasing water storage efficiency by reducing evaporation, and increasing water infiltration rate. By leaving crop residue after harvest, soil moisture content is improved.
"We are still concerned about getting the leftovers out of the way from the drought of 2012. At this time we would not anticipate a national corn yield above the trend," said Taylor. "Rather, we would expect a fourth consecutive year of below-trend crop, not as far below as in 2012 but still not up to par.
"While many farmers are concerned about the leftover problems that could be experienced during the 2013 growing season due to lack of moisture, they continue to find ways to grow crops to the best of their abilities in hopes of finding gold at the end of the rainbow.
Jennifer Carrico can be reached by phone at 515-833-2120, or by email at firstname.lastname@example.org.