University of Nebraska graduate student Rachel Stevens is breaking new ground when it comes to researching multi-hybrid planting. Now in her second year of research with Joe Luck, Nebraska Extension precision-ag engineer, she and fellow graduate student John Evans took to the fields in Saunders and Dodge counties, planting corn and soybeans in the rolling terrain.
Nebraska Farmer caught up with Stevens in early May, while she and Evans were planting two varieties of corn in Angela and Kerry Knuth's field near Colon, using a Kinze 4900 multi-hybrid planter. Operating on 700 acres of on-farm research this season, Stevens developed customized seeding prescription maps based on management zones in the fields.
For the Knuths, it's all about management. "The resolution at which we look at a field as well as collect data from a field has increased, allowing us to manage areas of a field independently, based on the data specific to the location," says Angela Knuth. "Seed companies have always had a vast arsenal of hybrids producers can choose from based on the hybrid traits and the environment it excels in." She notes that multi-hybrid planting would appear to be one way to capitalize by way of merging two existing technologies to better manage a field by allowing for seed trait adjustments within each field based on the environment of a location in the field.
"It might be challenging to have enough usable data to say using a single hybrid in a field is a yield-limiting factor," Knuth says. "There are so many factors that affect a crop throughout the growing season, so it is hard to determine actual cause-and-effect issues." She also says that it might be hard to quantify if the money spent on a multi-hybrid planter is going to result in increased yields and profits because of all of those multiple factors that are in play.
The earliest research on multi-hybrid planting was done at South Dakota State University research farms, beginning in spring 2012. In 2015, SDSU utilized the Kinze multi-hybrid planter that offers seamless planting between two varieties with so much precision that observers cannot tell by seed spacing where one variety ends and the other starts in a row. SDSU research most recently has focused on finding the correct varieties to perform under lowland and upland conditions. When farmers are experiencing optimal growing conditions, multi-hybrid planting may not pay off with higher yields. When there is greater variability in weather and soil types across the field, it may boost yields by as much as 5 to 8 bushels per acre on corn and 2 to 3 bushels per acre on soybeans, according to Peter Sexton, SDSU Southeast Research Farm supervisor.
Building on that initial research, Stevens says that corn research sites this year are being tested for optimizing hybrid placement for water availability. In soybean fields, researchers are taking a multiple-treatment approach for each site, specifically applying seeds treated with ILeVO to combat sudden death syndrome.
Last year's results from multi-hybrid planting trials were mixed, Stevens says. "All of our field sites received above-average rainfall, some as much as 10 inches more than the 10-year average," she says. "We really didn't have a need at any of these sites for a defensive hybrid with drought-tolerant traits. The majority of sites showed no difference between the two hybrids across zones," Stevens explains. "This is really the indicator to us that while we didn't see a benefit from using a defensive hybrid, we also didn't take a yield hit for using it either."
Stevens hopes that research over a larger area at more sites this year will provide useful results. "We know the technology is there; these systems are quite capable of switching between hybrids accurately as we move into different management zones," Stevens says. "When creating prescription maps, we are looking at as many data layers as possible for the field," she says. "In most cases, we are assessing multiple years of yield data, soil electrical conductivity and topography. For each of these sites, we are looking how these data layers are spatially correlated. If a high level of correlation is present, that layer was included in the clustering process." She notes that it is challenging to know what factors are most influential across a field, and the variables farmers are dealing with are compounded, creating additional complexity.
"Our goal is to assist in the decision-making process for producers, as they adopt this technology or as they take some steps to prepare for adoption down the road," Stevens says. "Creating the best possible prescription map could take several years of adjustments. There are things producers can be doing now, including collecting as many spatial data layers as possible, or conducting split planter research to compare hybrids across a field."