Last week marked the end of the line for corn planting on most farms north of Highway 20, Iowa State University (ISU) Field Agronomist Angie Rieck-Hinz said at a prevented planting meeting in Dows on June 4.

“We’re pretty much past that point for planting corn, just from a yield standpoint. We take a big hit,” she said. Planting date studies from ISU’s Northern Research Farm show yields for corn planted in mid-June are reduced 40% or more while harvest moisture increases 0.1% for each day of delay, adding drying costs to already strained crop budgets. 

“There’s still some guys who don’t have their corn in,” said Rieck-Hinz, noting a pop-up storm doused some...