Al Schafbuch said Iowa farmers are moving too slowly in adopting conservation practices that would help improve the quality of the state's rivers, streams and lakes.

With only about 7% of Iowa farmland planted in cover crops, "it will take 100 years to get this done," Schafbuch said. "We can't wait 100 years."

Schafbuch was referring to conservation practices needed to reach Iowa's goal to cut by 45% the nitrogen and phosphorus levels in waters that flow from the state to the Mississippi River, eventually contributing to a dead zone in the Gulf of Mexico. It's an area about the size of Massachusetts that is unable to support aquatic life during the summer months.

That's the kind of message farmers expect to hear from environmentalists. But Schafbuch, who farms near Dysart, was speaking during a water quality session at the Iowa Farm Bureau Federation's annual meeting Wednesday in Des Moines.

"We need to get urgent. ... We need some enthusiasm from farmers who are not on board," Schafbuch said. "Let's make something happen."

Whether farmers are moving fast enough to adopt conservation practices is likely to again become a source of debate as the state Legislature convenes in January.

Conservation, environmental and some agriculture groups want lawmakers to pass a sales tax that could be used to accelerate the funding available for water quality initiatives.

About 60% of Iowans supported a constitutional amendment in 2010 creating a natural resources and outdoors fund, but lawmakers have failed to pass a sales tax to provide funding. Increasing the sales tax three-eighths of one cent would raise an estimated $188 million annually.

Matt Lechtenberg, water quality coordinator at the Iowa Department of Agriculture, said new funding the Iowa Legislature approved last year will help the state target practices that can cut nitrogen losses in waterways.

Lawmakers will make $156 million of $282 million appropriated over 12 years available for bioreactors, saturated buffers and other practices that cut nitrogen leaching from farm fields.

Already, work is underway to create 30 more wetlands, which can cut nitrogen levels in half. The state now has 90 wetlands. "We're scaling up efforts," Lechtenberg said.

Iowa Farm Bureau officials said farmers are making progress. For example, a survey showed farmers planted cover crops on 1.5 million acres and used no-till practices — not tilling the ground before planting — on about 40% of the state's soybean acres.

A panel of water quality experts said research is underway to better gauge the economic and soil benefits of cover crops and other conservation practices. And farmers at the meeting said they're seeing results.

"We’re convinced cover crops are improving our yields, especially on soybeans," said Jeff Cuddleback, who farms in Washington County. "There's no yield loss, and a yield gain from it."

Matt Helmers, an Iowa State University agricultural engineering professor, said some farmers' resistance to conservation practices is cultural.

"It's important for people like yourself to speak up and use your voice to say, 'We can do better in some areas,' " said Helmers, also director of the Iowa Nutrient Research Center, a state nutrient management research group.

This year's harvest, made difficult by rain and snow that may have prevented farmers from doing fall tillage, might give farmers an opportunity to try planting beans into corn stalks.

"I've started that discussion at home over Thanksgiving with my uncle who farms our family farms," Helmers said. "I didn't get far. But I'm still trying."