“We’re quite far behind in Missouri, especially compared to the last four to five years,” says University of Missouri Extension specialist Bill Wiebold.

The April 27 USDA crop progress report shows only 20 percent of the state’s corn crop planted, compared to 44 percent last year at this time.

Early planting sets the stage for good yields. As May begins, delays turn into slight yield losses, as shown by five years of data for central and northern Missouri.

Yield drops as much as 20 percent when corn is not planted by the end of May, Wiebold says. Yield loss increases at a faster rate when planting moves into June.

Wiebold says delayed planting in the Bootheel region has significantly lowered the state’s average. Planting there is 16 percent complete, far below the amount typical for late April.

But those numbers can change quickly if weather is favorable.

“We can plant a lot of corn in a short time in this state,” Wiebold says. “We’ll be in reasonably good shape if we get a lot of corn planted in the next week.”

USDA reports that Missouri farmers expect to plant 3.3 million acres of corn in 2015, the lowest amount since 2010. This is down 0.2 million acres from 2014.