By Dick Sloan
The Iowa Nutrient Reduction Strategy treats farmers honestly. I see it as a very empowering document for farmers to embrace. The science that has increased our productivity dramatically in our own lifetimes is showing everyone that the problems we have to address are not caused by overfertilizing our crops.
As illustrated by Table 2 of the strategyís executive summary, improving management of timing and source are among the least effective and most variable options for reducing leakage. Nitrogen application rate and use of nitrification inhibitors are slightly more effective, and when combined with timing and source efficiencies, should be justified on economic grounds.
So if the Gulf Hypoxic Zone isnít a result of excess applications, are we ďoff the hookĒ? Hardly. Think about what youíve witnessed and participated in as weíve moved from farm systems based on long rotations, livestock and perennial pastures to rectangular patches of corn and soybeans. Some places, itís just corn.
Iím not telling you how to farm and neither does the strategy. But it gives you options. Good, responsible options.
You can return to more traditional farming systems and embrace perennial crops, grazed pastures and extended rotations, as many organic farmers have found profitable. If this is not your choice, please respect that they are not the problem. Conventional farming practices are the problem.
You can decide if you need a wetland or biofilter to convert your leaking nitrates to nitrogen and oxygen gas. Wetlands could provide some buffer to flooding and habitat to a few species that have called Iowa home for a few thousand years. And a little basic erosion control should meet phosphorus reduction goals.
I am afraid some policy changes will be mandated if we donít voluntarily plan to pull our tile outlets out of the streams. Current policy encourages farmers to maximize dollars per acre farmed while neglecting the invaluable resources degraded in the process.
Or if you can embrace some of the practices of the soil health movement, you may be able to reduce the leakiness of your farming system. When nothing is growing in your soil seven months out of the year, water and nutrients will drain out of the system and important microorganisms will starve. Cover crops can cost $30 to $50 an acre for seed and planting but should gather nutrients from soil to build organic matter and resilience. Some soils benefit from strip-till, which can complement cover cropping as my strip-injected liquid hog manure applications do.
My plan is to grow multispecies, nutrient-scavenging cover crops on all of my no-till corn-corn-bean rotated acres. Iíll also grow 20 acres of cereal rye in a bean-rye/legume, cover crop-corn three-year rotation. Iím confident I will build soil quality faster this way on some small fields of my operation, improving profitability, sustainability and yields of corn and beans.
It qualifies as a resource-conserving crop in the Conservation Stewardship Program by drastically reducing energy requirements to produce commercial fertilizer. I will use the rye for my cover crop seed or trade some with a neighbor for some oats for diversity.
Use of third crops in targeted locations drastically could improve soil erosion problems in Iowa, opening up possibilities for summer construction of waterways and berms.
Whether farmers will implement the strategy depends on cues we get from our communities. If we decide that money is the only arbiter of success, then I think we are denying some of the responsibilities that go with our rights.
We canít continue to farm the way we have been farming.Dick Sloan, a Buchanan County farmer, is a farmer partner with Iowa Learning Farms and a member of Practical Farmers of Iowa. Comments: firstname.lastname@example.org