The U.S. Department of Agriculture chose to fund two Kansas State University agronomy professors for their participation in a sustainable agriculture program.
The program, a coalition of around 100 university, non-profit and government scientists at 35 institutions, awarded K-State more than $200,000 to study cover crops.
The two agronomy professors, DeAnn Presley, Ph.D., also an environmental soil science and management specialist, and Peter Tomlinson, Ph.D., an extension specialist in environmental quality, were chosen for this five-year study, which aims to increase profitability, resilience and sustainability. By using cover crops and technological tools and measurements, the study hopes to determine the advantages and/or disadvantages of using cover crops.
Cover crops are plants, such as legumes, grasses and grains that are grown to improve soil and protect it from wind, increase water and nutrient retention, and help with pest management. Using these crops allows for more climate-resilient production.
“What interested me in the project is the opportunity to improve the science behind cover crops,” Tomlinson said. “This project will provide critical answers to questions producers ask about how to adjust their management systems as they integrate cover crops into their crop rotation.”
According to K-State, the researchers are part of a group that makes up a sustainable agriculture team (http://precisionsustainableag.org/) designed to enhance research, education, and extension through real-time data flow, edge and cloud-based platforms, decision support tools, and on-farm monitoring systems. By focusing on cover crops and conservation tillage, the project will contribute to both improved profit for farmers and reduced environmental impacts of agriculture.
There will be several facets to the study. One facet will determine the amount of nitrogen that should be used. During the study, researchers hope to find out how a farmer would adjust his or her input, up or down, if he or she used a cover crop. Researchers will also be examining water retention, looking for insects and counting weeds. Three farmers who already practice no-till, but do not use cover crops, will be chosen for the study. In addition to the scientific aspects of the study, the farmer will be assigned a sociologist to study how and why the farmer prefers one method over the other and other variables related to the study.
Each of the institutions will use similar variables, including five-acre lots, control and experimental groups and state-of-the-art, experimental tools. Each institution will choose two out of three crops; either corn, soybeans or cotton. K-State chose soybeans and corn.
“The crops are going to need to be attended to,” Presley said. “I think of cover crops as an investment.”
Through previous research, Presley found cover crops were good for the soil and erosion, but she did not see any increase in yield. Along with healthier soil, renting out the cover crop to cattle and sheep ranchers adds extra income for the farmer, and the animals benefit from foraging through these fields.
Along with measuring yield, the cover crops’ effect on weeds will also be measured. Presley said pigweeds and their relatives have become detrimental to soybean crops in Kansas. She is hoping the cover crops will help decrease this weed. Some pigweeds, she said, have become herbicide-resistant. The study will determine whether cover crops will curtail this noxious weed.
“We’ll be able to cover (in the research) from the Atlantic Ocean to the Rocky Mountains,” Tomlinson said. “We’ll be looking at nutrition statuses of the crop in real-time.”
The study will use one grass and one legume cover crop, but, Presley said, cover crops that work well in Kansas include triticale, wheat, buckwheat, rye, sunflowers, radishes, pumpkins, canola, cowpeas, turnips and oats. The list also includes cruciferous vegetables, cabbages and mustard plants. As to which is best for each crop, it all depends upon the grain planted before the cover crop is planted and the timing of the harvest. Several cover crops inject much-needed nitrogen into the soil for the next crop. Presley recommends placing cereal rye, barley or legumes between the corn and soybean crops.
“Deciding on a cover crop is like buying a used car,” Presley said. “There are a lot of choices, each with different strengths and weaknesses.”
There are many cover crops to choose from - whether a vegetable, grain or flower. Less than 5% of farming acreage in the Sunflower State employ cover crops.
“The interest in cover crops is very high,” Presley said. “I do notice that people who like cover crops are no-till farmers. But you don’t have to be. No-till is like a diet. Cover crops are like exercise. Doing both is great, but you don’t have to do both.”