Drought danger rises in Iowa

What many Iowans hoped would be a million-dollar rain Sunday night turned out be worth a lot less in most parts of the state.

The quarter-inch of rain that fell over much of Eastern Iowa will dissipate through evaporation and transpiration in about 24 hours, leaving Iowans to face another hot, cloudless week, state Climatologist Harry Hillaker said.

While Hillaker stopped short of invoking the “D” word, he said much of the state is moving rapidly toward drought conditions.

“The trouble is almost exclusively due to rainfall deficits the past five weeks,” he said.

The statewide average rainfall for March through May, 9.45 inches, was barely below the normal average of 10.22 inches. But Hillaker said a succession of sunny, breezy days with low humidity - while pleasant for people and animals - has hastened the drying of farm fields.

“A big portion of the state needs water. It's more serious than a lot of people realize,” said Bill Northey, secretary of the Iowa Department of Agriculture and Land Stewardship.

For a third straight week, the condition of Iowa's corn and soybean crops deteriorated, according to the report issued Monday by the USDA's National Agricultural Statistical Service.

On Monday, 8 percent of the corn crop was rated poor or very poor, up from 5 percent the preceding week. The percentage of corn rated good or excellent fell from 75 percent to 67 percent, while the same measure for soybeans fell from 71 percent to 62 percent.

As of Sunday, topsoil moisture was rated either short or very short in 66 percent of the state, while subsoil moisture fell into those same categories in 59 percent of the state.

Iowa State University Extension climatologist Elwynn Taylor, an expert on the impact of drought on crops, said he has received 50 phone calls in the last five days about corn leaves rolling to conserve moisture - the most visible crop symptom of drought.

“At this stage of development, for every 12 hours that the leaves are rolled, it cuts potential yield by 3 percent,” said Taylor, who bases his assessment on 30 years of observation.

Kurt Hora, who farms in Washington County, said corn leaves are rolling in some of his fields.

Hora, a director of the Iowa Corn Growers Association, said the quarter-inch that fell Sunday night on his farm was the first rain he's had since Memorial Day weekend.

Even so, he said, his crops retain good color, and the rainfall shortage has encouraged his corn to sink deep roots - two factors that contribute to Hora's continued optimism for at least normal yields this year.

Jerry Mohr, another director of the corn growers group, said he has observed no corn leaf rolling in his fields in Scott and Clinton counties.

His crops were “looking better” Monday morning after four-tenths of an inch of rain fell on them Sunday night, Mohr said.

Taylor said this spring's dry conditions are not nearly as severe as those that prevailed in the memorable drought of 1988.

“By this point in 1988, the yield potential of the corn crop had already fallen more than 20 percent below the trend line,” he said. Iowa's average yield that year was 84 bushels per acre, down from 137 in 1987 and 135 in 1986.