Rain and wind is washing away enough of Iowa's fertile topsoil to potentially reduce crop yields by $1 billion, so researchers are working to develop a better way to measure erosion.
The Des Moines Register reports researchers think parts of Iowa could be losing up to 12 times more soil that government reports suggest.
Iowa State University professor Rick Cruse is leading a team developing a new method to measure erosion's impact that could paint a grim picture.
Some of the most severe erosion happens in western and southeastern parts of Iowa.
State Agriculture Secretary Bill Northey says erosion may be getting worse because conservation programs have been scaled back.