8:43 a.m., Dec. 14, 2009----Greg Binford spends his days in college laboratories and cornfields miles from the Chesapeake Bay but his research has a direct impact on the water quality of this estuary, which is home to more than 3,600 species of plants and animals and more than 16.6 million people.
A plant and soil science specialist for University of Delaware Cooperative Extension, Binford works to optimize crop production for farmers while minimizing the impact on the environment of the fertilizer and manure nutrients essential for crop growth. Binford also serves as an associate professor in UD's Department of Plant and Soil Sciences.
Earlier this year, he received a $550,000 grant from the U.S. Fish and Wildlife Service to develop a nutrient management system that will result in less nitrogen leaving cornfields and entering the Chesapeake Bay while improving overall profitability to growers.
The key, says Binford, is to revise the nutrient management plans currently used by growers so that there is a feedback mechanism in place that allows for an evaluation at the end of the season.
“Nitrogen management is one of the greatest challenges during the production of corn, notes Binford. “The challenge is in determining the difference between the optimal rate of nitrogen and any rate above this optimal.”
“Nitrogen can be lost from soils relatively easily and the availability of nitrogen from organic sources is strongly weather dependent,” adds Binford. “Growers can unknowingly apply too much nitrogen since plant health and grain yields do not change when rates applied are greater than the economic optimum rate.”
On the flip side, applying too little nitrogen can be very detrimental to yields so growers are reluctant to fine-tune their management program unless they can quantitatively evaluate it.
And that's where Binford's research study comes in. The ultimate project goal is to develop a performance-based nutrient management system. The study uses 300 fields as on-farm research plots and involves the cooperation of more than 75 farmers from Kent and Sussex counties as well as areas of Maryland.
The Chesapeake Bay watershed is comprised of some nine million acres of farmland so even growers who aren't directly on the Bay or its tributaries can have an impact on water quality.
The project kicked off in spring when Binford lined up a sufficient number of growers to commit to the project. In early August, aerial images were taken to assess each field. From the air, corn stalks that might be deficient in nitrogen appear yellow. However, Binford notes that there are other reasons for such stalk yellowing. These images were used to plot out research sites. Both stressed (yellowing) areas of the field as well as areas that appeared healthy were chosen.
Susan White-Hansen, precision farming specialist at UD's Carvel Research and Education Center in Georgetown, developed the protocol for selecting the sampling locations from each of the aerial images.
The aerial photography work has been the most nerve-wracking part of the project for Binford. “We had a narrow timeframe in which to complete the photo sessions and rain kept our plane grounded many days,” recalls Binford. “I breathed a sigh of relief when we got our last photo session in.”
The end of the crop season, late August to early September, was the hectic time for Extension associates Shawn Tingle and Warren Willey, who were joined by private consultants who assisted with the project. Under Binford's direction, this team fanned out into all 300 fields to utilize an innovative test based on the concentration of nitrate in the lower part of the cornstalk. If concentrations are above a recommended value it indicates that excessive nitrogen was applied during the growing season.
Binford developed this specialized test in the early 1990s and it has since been widely evaluated in other research projects. Although the test method is popular with researchers, it hasn't been used much in production agriculture.
This summer marked the first growing season for the three-year project. Although Binford already has preliminary results he doesn't want to make recommendations based on one year's findings.
“Because it's a biological system, weather and management will greatly affect the amount of nitrogen available to the crop,” says Binford. “Therefore, it's important that drastic changes not be made in nitrogen management after only one or two years of collecting stalk nitrate results.”
“Dr. Binford's research is making a valuable contribution to the coordinated efforts of farmers, Extension advisors and researchers to put new diagnostic tools into place on the farms in the Chesapeake Bay watershed,” said Tom Sims, T. A. Baker Professor of Soil and Environmental Chemistry and deputy dean of the College of Agriculture and Natural Resources. “His studies represent the application of our understanding of plant biology to the practical problems farmers face in managing nitrogen in an environmentally sustainable manner. Greg is a national leader in nutrient management and I have no doubt the results of his latest research grant will be adopted and benefit agriculture while protecting the environment.”
“Susan White-Hansen's contributions have been critically important to this study as the aerial remote sensing technology she developed should provide a means to diagnose and correct nitrogen management problems on thousands of acres of farmland in the Bay watershed,” noted Sims.
“This research is critically important to Delmarva farmers,” said Jan Seitz, associate dean and director of UD Cooperative Extension. “At monthly Friends of Ag meetings and other agricultural events I've spoken to many farmers who are eagerly awaiting the results of Greg's research. Delaware's farmers are stewards of the land who are committed to best practices in nutrient management.”
Binford hopes that local growers gain confidence in their management practices and reduce nitrogen usage by systematically using the test method that he has developed. Such efforts will help not only the growers' bottom line but the health of the Chesapeake Bay.
“We need to create a paradigm shift in our current nutrient recommendation system,” says Binford. “It's my goal to see my research contribute to that shift in thinking.”
Article by Margo McDonough
Photo by Danielle Quigley