This spring has been a blur of activity for the Jones family on their farm near Greenfield in Adair County. Like most Iowa farmers, they hustled to plant corn as soon as their fields were dry and ready, then followed up with soybeans. At the same time, they worked through calving season, caring for their cows and making sure the new calves got off to a good start.

But with their corn barely emerged, their soybeans just starting to poke through the ground and a few cows still left to calve on their ...