Saving our dirt

By The Gazette Editorial Board

--

Dirt. Many of us take it for granted. We shouldn't.

Iowa is home to much of the world's most fertile topsoil. It's the basis of our highly productive farm economy. Good dirt feeds the world. But this priceless resource is being depleted despite better conservation efforts by many Iowa farmers.

More frequent heavy rainfalls as the climate changed in recent years have speeded up erosion, as much as 12 times the “tolerable” rate of 5 tons lost per acre per year in some areas, new Iowa State University research shows. That's troubling news on top of what we've known for years: Average topsoil depth statewide is about half of what it was when cultivation began. And topsoil quality, states a 2009 ISU report, has declined substantially after decades of intensive farming practices.

With recent high commodity prices, some farmers are inclined to till more land that shouldn't be in row crops - which can further increase erosion problems.

By itself, nature takes 200 or more years to replace an inch of topsoil. Comprehensive conservation measures by farmers and landowners can quicken replacement, as well as slow erosion. Such expanded practices require more upfront investment. Farmers should participate, but public policy changes and more assistance are needed if we want to save Iowa's dirt.

n Comments: thegazette.com/

category/opinion/editorial or

editorial@sourcemedia.net