Crops are not the only things wilting in the sweltering summer of 2012; cattle, the largest animals on the farm, are also under stress.
Some cattle producers are protecting their herds by putting them under hoop barns, which are gaining acceptance across the Midwest. The simple structures are made by stretching fabric over strong metal arches, or hoops, providing vital shade and protection from rain, snow or sun.
Tanner Rowe, a cattle producer near Dallas Canter, Iowa, has found hoop barns give cattle a much-needed break from sweltering heat.
"On a day like this their body temperature can be 20 degrees warmer than the outside temperature, and that's pretty tough on a 1,300-pound animal," Rowe said.
Most of Rowe's heard lazed in the shade under two large hoop barns he'd built a couple of years ago.
"(The hoop barns) definitely help with the creature comforts," Rowe said. "The cattle are much more comfortable. I'd have them all inside today, but I just don't have the room in the buildings to do it."
Originally, hoop buildings were used for pigs in Canada. More and more, cattle are living under a roof - either a hoop barn or other covered structures that protect the animals and the environment.
Iowa is a leader in livestock housing research. A study found that nearly 700 hoop barns were used for cattle in Iowa last year, according to Mark Honeyman at Iowa State University.
"I see hoop barns all over Iowa," Honeyman said. "We are, in effect, feeding cattle under a big tent."
Aside from just cooling off cows, housing cattle can have environmental benefits, too.
"By feeding cattle in a hoop barn or other covered ways, the potential for runoff into Iowa's streams, ponds and lakes is greatly reduced," Honeyman said.
Iowa State University has had good results with hoop barns on its demonstration farms, although the fabric roof eventually has to be replaced and two of them burned up in a fire this month. A typical hoop barn for feeding cattle could cost around $200,000.
Near Washta, Iowa, Brent Bryant and his father keep 2,000 head of cattle under six hoop barns on their research farm. For eight years they have also sold hoop barns through their company, Hoop Beef System.
"As of July 1, we'd already sold more hoop barns to customers across the Midwest than we did all of the last year's full sale year," Bryant said, "It's definitely a concept that's popular, demand for it is growing."
On a day on which Washta is under a heat advisory, hoop barns were keeping the cattle in the shade, and ventilated, just as they were designed.
"Well, here we don't really see much of an impact on the cattle," Bryant said. "Their intake or how much feed we feed them - we have not changed that due to the heat, and we don't run any sprinklers, don't run any fans in. (But) our cattle have stayed comfortable, and that's something we're really thankful for."
Heat stress reduces profitability - last summer it killed up to 4,000 cattle across Iowa. Others lost weight and went to market lighter or required farmers to bulk them up. Bob Bryant, Brent's father and co-owner of Hoop Beef System, contends that hoop buildings enhance income and beef quality.
"The cattle have less stress when they are in the hoop barns, because of that we get a little higher yield on the cattle when they're harvested, and we get probably a 10 percent better grade on the meat because of the lack of stress on the cattle," Bob Bryant said.
With cattle increasingly spending most of their lives under a roof, harsh weather extremes are diminished, and the elder Bryant is bullish on Midwest beef production. For producers who have switched to these covered feedlots, the problem now is not how high the temperature will get, but how high will the price of corn go.