Wet weather has caused farmers to delay planting corn as intermittent rain prevents ideal planting conditions.

The Farm Service Agency’s Mahaska County Executive Director Joe Rieck said that as of Sunday, May 5, taking into account that day, approximately 18 percent of the projected corn acres had been planted. Rieck said farmers also planted on May 5 and 6, raising the percentage to approximately 38 percent for Mahaska County.

Rieck said these findings are less than last year and the five-year average for the county. This year there have been seven good days for planting corn: April 16 and 17 and May 2, 3, 4, 5 and 6. Between April 17 and May 2, it was too wet to plant, Rieck said.

Rieck said the planting situation is similar to last year. Starting on May 11, there were 10 days of dry conditions and all the planting got done. Rieck said he is hoping for similar stretch this year.

“We want to beat the next storm system coming through,” Rieck said.

A check of the 10-day weather forecast at www.weather.com shows chances of rain of 30 percent or greater for seven days between May 8 and May 17.

Rieck also said the corn that was planted on April 16 and 17 has emerged and is looking well.

Iowa State University extension field agronomist Mark Carlton works in Mahaska County and 10 other counties in Southeast Iowa. He said rain twice or three times per week has hampered corn planting.

Data collected by Iowa State shows that corn planted by May 10 generally suffers no yield loss, Carlton said. Between May 10 and May 25, fields suffer a possible 1 percent loss in yield per day. After May 25, the yield loss per day tends to increase, Carlton said.

Planting in the mud is not a good solution, because it often prevents roots from growing sideways. Carlton said if it continues to rain, it doesn’t make much difference if the corn has been planted in the mud. The concern for planting in wet conditions is that a dry July and August would likely cause lower yields.

Carlton’s advice to farmers is to wait until the soil is right. He said farmers may reduce yield more by planting in the mud than by planting at a later date.

The effects of the winter are also continuing to show. Carlton said soil temperatures are approximately three weeks behind.

Herald Staff Writer Wes Kappelman can be reached by e-mail at news2@oskyherald.com