Early-season weed control widens application window for a post glyphosate application
As the growing season comes to an end, many soybean growers are looking ahead for profitable and effective treatments to maintain clean fields next spring. While some may find it more convenient to use either a fall soybean herbicide program or a post emergence only program, the impact of early-season weed competition in both those programs can limit yield potential and ultimately your bottomline. The use of a pre-emergence herbicide in the spring protects your investment by providing residual control during critical crop development stages and extends the application window for a post-glyphosate application, serving as an effective treatment that lasts into the growing season.
Allocating a spring-applied residual herbicide treatment to your soybean acres will provide weed protection during the critical crop development stages. By eliminating weeds early in the season that compete with soybeans for vital nutrients and moisture, growers can protect valuable yield potential that may be lost or reduced with a later glyphosate application.
Palle Pedersen, assistant professor of agronomy and soybean specialist at Iowa State University, comments on his experience witha pre-emergence herbicide. “We saw a nice response where a pre was used in 2008. Because of the excessive floods we have in Iowa, no one was able to drive in the fields. We know there is early-weed competition for both soybeans and corn. Because we were able to apply a pre in most of our fields, we were able to manage weeds before yield was lost from weed competition this year."
An effective residual herbicide, such as Prefix®, widens the application window that allows soybean growers to time their post emergence glyphosate application with greater flexibility despite weather conditions.
“We will try to use a pre- on all our high yield research studies next year, because we get a longer window in the spring and when you get into a wet scenario like in 2008, we will not lose any yield from weed competition," stated Pedersen.
As shown in the graph below, soybean growers can receive yield benefits from using Prefix as a pre-emergence treatment, regardless of the glyphosate application timing. Prefix widens the application window, reducing the risks associated with applying glyphosate too early or too late.
Much is at stake when applying post applications of glyphosate too late or too early. According to Dr. Bryan Young, professor of weed science at Southern Illinois University, “Applications applied too late (assuming no residual herbicide was used) can quickly approach yield losses in excess of ten percent, not to mention the risk of reduced weed control from trying to spray weeds that are too tall. The applications that are performed too early may simply require another glyphosate application."
Glyphosate- and ALS-resistant weeds can rob yield potential from growers and reduce profitability. Using a non-ALS, non-glyphosate pre-emergence herbicide widens the application window for glyphosate, giving growers a better opportunity for a high-yielding harvest. Prefix offers an alternate mode of action to target problem weeds and is a timely spring application that can protect the crop when control is neede