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Farm poll: Room for improvement in nutrient management strategies

July 18, 2014  by J. Gordon Arbuckle Jr. & Laura Sternweis

The Iowa Nutrient Reduction Strategy sets ambitious goals for keeping agricultural nutrients out of the state’s waterways. To reach the reduction targets, Iowa farmers and their advisers will have to work together to improve nutrient management strategies, according to the Iowa Farm and Rural Life Poll.

Nitrogen management is important to Iowa agriculture. Most of the nutrients that are applied to agricultural lands serve their intended purpose of increasing crop yields. However, substantial quantities flow from fields into waterways, where they degrade water quality in Iowa’s streams, lakes and other water bodies. The loss of nitrogen and other nutrients from agricultural activities leads to economic and environmental costs in Iowa and elsewhere, since some of that nutrient flow eventually finds its way into the Mississippi River and then the Gulf of Mexico.

A new farm poll report presents data on the types of nitrogen management practices that Iowa farmers are using, the methods they use to determine fertilization rates, and the information sources they look to for advice on nutrient management. It was developed primarily to support the efforts of ISU Extension and Outreach and other agricultural stakeholders as they strive to help farmers meet nutrient loss reduction targets set in the Iowa Nutrient Reduction Strategy, said J. Gordon Arbuckle Jr., a sociologist with Iowa State University Extension and Outreach. Arbuckle co-directs the annual poll with Paul Lasley, also an ISU Extension and Outreach sociologist.

“Some of the most innovative and effective nitrogen management practices, such as nitrogen inhibitors and calculators for determining optimal fertilization rates, are not used by many farmers, and large percentages of farmers are not familiar with them,” Arbuckle said. “Farmers and farmland owners need to learn more about which practices are most effective for their particular situations. They will have to set nutrient management goals and then implement the right mix of practices to reach those goals.”

The data comes from the 2012 Farm Poll, which measured farmers’ knowledge and use of various methods for managing nitrogen based on the 2011 corn and soybean crop season. Nearly 1,300 farmers participated in the poll, and Arbuckle and graduate student Hanna Rosman have published the findings in a new report, Iowa Farmers’ Nitrogen Management Practices and Perspectives.

Another important finding was that fertilizer suppliers are the advisers that farmers tend to look to first for guidance on nutrient management. “These and other stakeholders that provide products, advice and technical assistance to farmers should shoulder some responsibility to help their clients set and meet nutrient loss reduction goals,” Arbuckle said. “They must be prepared to provide information and technical assistance on the most effective management and structural practices to reduce loss of nitrogen and other nutrients into Iowa waters.”

Arbuckle said that more than half of the survey participants believed that farmers over-apply fertilizer to ensure yields. At the same time, 75 percent thought the amount of fertilizer that Iowa farmers apply is “about right.” This means that many farmers who feel that farmers use excess fertilizer to ensure yields also believe that the amount applied is about right. These results support anecdotal evidence that applying excess nitrogen as yield insurance is a common practice.

“With variation in weather, soil types, time constraints and other factors, it can be difficult to calculate and time application to ensure that the exact amount of nitrogen that plants will need is there when they need it. The perceived economic risks of under-applying are high, and these results suggest that, for at least some farmers, over-applying, as insurance, is simply part of farming,” Arbuckle said.

In 2013, the state of Iowa released the Iowa Nutrient Reduction Strategy, a science and technology-based framework to guide actions that reduce the loss of nutrients to surface water. It was developed through the collaboration of Iowa State University, the Iowa Department of Agriculture and Land Stewardship, the Iowa Department of Natural Resources and USDA’s Agricultural Research Service and Natural Resources Conservation Service.

Iowa Farmers’ Nitrogen Management Practices and Perspectives  (PM 3066) and previous Iowa Farm and Rural Life Poll summary and topical reports are available to download from the ISU Extension and Outreach Online Store,, and Extension Sociology,

Conducted every year since its establishment in 1982, the Iowa Farm and Rural Life Poll is the longest-running survey of its kind in the nation. ISU Extension and Outreach, the Iowa Agriculture and Home Economics Experiment Station, the Iowa Department of Agriculture and Land Stewardship, and the Iowa Agricultural Statistics Service are all partners in the Farm Poll effort.

J. Gordon Arbuckle Jr. is a sociologist with Iowa State University Extension and Outreach who also co-directs the annual Iowa Farm and Rural Life Poll. Laura Sternweis is an Extension communications specialist at Iowa State University.




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