Q&A: Curt Zingula on the pluses and minuses of tillage

Curt Zingula is a Linn County grain farmer and a recipient of the Iowa Farm Environmental Leader Award, which is given by the governor's office, the Iowa Department of Agriculture and Land Stewardship, and the Iowa Department of Natural Resources.

What practices do you use to conserve soil and reduce loss of nutrients on your farm?

I conserve soil mainly by reducing tillage and supplementing that with some contour planting and terraces. Maintaining grass waterways is also important for reducing gullies and catching eroded soil before it leaves the farm.

Nitrogen fertilizer is managed with an additive that targets and inhibits the bacteria that break down nitrogen fertilizer into nitrates. Also, I'm doing a saturated buffer and cover crop side-by-side demonstration plot to analyze those conservation methods for nitrate reduction.

Could you expand your conservation practices, and would you if more cost-share funding were available?

I expect to expand my conservation practices along the line of nitrate reduction. I'll move forward with the results I obtain from my four-year demonstration plot data with a close eye on utilizing saturated buffers. In addition, I'm currently planning about 20 acres of pollinator habitat.

Expanding cover crops as a conservation practice will depend a lot on cost shares. Cover crops on my entire farming operation would cost tens of thousands of dollars annually above realistic yield increases.

What practices do you think hold the most promise for reducing nutrient pollution to acceptable levels?

Phosphorous pollution will be reduced the most by reducing tillage. Eighty percent of the P leaving crop farms does so attached to an eroded soil particle. Phosphorous from livestock waste can be managed better with impervious containment structures and then injecting that waste into the soil.

Drainage tile has been blamed for increasing loss of nitrates from farm fields. Do you believe that is true and, if so, can farmers get by with less subsurface drainage without greatly reducing yields?

There's no doubt that subsurface drainage tubes (tile) remove nitrates.

However, it's sad how so many people turn a blind eye to the many benefits of tile. Tile reduces surface runoff and the erosion it causes. Erosion moves phosphorous to our streams and lakes. Surplus water leaving a tile outlet is clear, while surplus water washing off the surface of land can be chocolate brown with sediment. Tile allows soil to warm and dry more quickly by replacing water saturation with air.

That result allows farmers to reduce the tillage they've used in the past for drying and warming seed beds. Reducing tillage allows organic matter to build and that, in turn, reduces flooding by increasing rainfall holding capacity. Every consumer, not just farmers, benefits from the higher yields resulting from tile.

It's also important to note that precipitation has been increasing steadily for several decades, with no change in sight. Areas that I avoided installing tile a quarter of a century ago are now becoming a problem with lower yields due to saturated soils causing denitrification (nitrogen lost to the atmosphere).

Would you favor a three-eighth-cent increase in the sales tax to provide a stable source of funding for expanding conservation practices in Iowa?

The three-eighth-cent sales tax increase was voted upon and passed by a majority of Iowans. In my opinion it's the will of the people and needs appropriate respect.

What level of farmer participation will be required to reach the 45 percent reduction goals established in the state's nutrient reduction plan?

About 110 percent participation! The EPA's goals are lofty indeed, but I guess that's what goals are meant to be. However, I believe the phosphorous goal stands the best chance of being obtained because tillage reductions are steadily being implemented and livestock waste is more commonly injected into the soil.

With nitrate reduction, the cost of reaching the EPA's goals will be tremendous and therefore could take decades to accomplish. The good news is that many methods of reducing nitrate pollution are being explored and better solutions appear forthcoming.

What is your opinion of the Des Moines Water Works lawsuit that seeks to regulate discharges from tile drainage districts in northwest Iowa?

I think one word describes the DMWW and its director, Bill Stowe — grandstanding. Numerous entities, both public and private, are contributing to nutrient reduction practices and doing so mostly anonymously.

We also need to understand that Stowe's goal is to require federal discharge permits on all tile outlets, not just those in northwest Iowa. This goal has no chance of working. Few outlets are publicly recorded, and many combine multiple farming entities.

Federal permits with their associated costs, planning commitments and monitoring would turn landlord against tenant and neighbor against neighbor. That would come in addition to the spending and verbal war we now expect between the agriculture community and the environmental community in pursuit of winning the lawsuit.