Midwest soil has been suffering from drought since early 2010, and a University of Missouri researcher says it may take at least two years for crops and soil to recover.
Randall Miles, associate professor of soil science at the MU School of Natural Resources, found soil in the Midwest is dry down to as deep as 5 feet, where the roots of the crops absorb moisture and nutrients.
"I wouldn't count on a full recovery of soil moisture any time soon," Miles said. "Even if parts of the Midwest receive a lot of snowfall and rain this spring, it will take time for the moisture to move deeply into the soil where the driest conditions exist."
In 2012, Miles found that some roots had to go down as much as 8 feet to extract water. Typically one foot of soil holds 2 inches of water. To recharge completely, a fully depleted soil would require about 16 inches of water over normal precipitation amounts.
Testing the depths of soil moisture around Missouri, Miles found that parts of the state where Hurricane Isaac dropped extra rainfall were wet in the first few inches of soil, but dry below that level. While that moisture helps for a short while, Miles said the moisture will evaporate with just a few days of high winds.
"In order for the soil moisture to return to a normal state this year, the rain and snow would almost have to come continuously," Miles said. "The weather would almost have to be like the precipitation found in London, coming down light and slowly to minimize runoff."
In addition to soil moisture being affected by the drought, Miles said that it could take two years of good rains for microbes and insects to recover, as well as barge traffic on the Mississippi and Missouri rivers.
"The soil moisture will recharge with a hydrologic process where water moves downward from surface water and fills in the pore space found in the soil," Miles said.
Along with the growing interest in biomass energy crops as renewable alternatives to fossil fuels comes a growing list of questions from corn and soybean farmers about what it will cost them to switch.
University of Illinois agricultural economist Madhu Khanna developed a customizable online calculator to eliminate some of the guesswork and help farmers make the decision.
"We've been doing calculations on what it would cost to produce energy crops in Illinois and other states for quite some time, and we realized that it could be useful to people who want to be able to calculate what these costs would be on their own farm," Khanna said. "We wanted to create a calculator so farmers would be able to make their own assessment."
The feedstock cost and profitability calculator can be found at miscanthus.ebi.berkeley.edu/Biofuel.
After selecting a baseline crop that they are currently farming, users provide specific information about their expenses, yields and inputs.
"They can customize the costs based on what their current farming operation looks like, what their current returns are on the land that they are thinking about converting and learn what it would cost to grow an energy crop on it instead. They can decide at what price it might be feasible for them to produce an energy crop," Khanna said.
This first version of the online calculator includes data for only Illinois, Michigan and Oklahoma.
"We presented these three states as illustrative," Khanna said. "We looked at poplar, miscanthus, switchgrass, prairie grass and stover. They behave differently in different parts of the country, so this initial calculator shows the contrast between three very different climate and rainfall regions."
-- Compiled by Herald-Whig Staff Writer
Deborah Gertz Husar