Doug Gross

In Iowa we beg people to put buffer strips along our rivers and lakes to keep them relatively clear of sediment. It doesn’t work. Farming the road ditches has become a popular practice, as any motorist with his eyes open can see. It shows up in our lakes — the mud is strangling lakes all over Northwest Iowa such that they might not see another century — and eventually in a huge nitrified dead zone in the Gulf of Mexico.

By ART CULLEN