When commodity prices are favorable, double cropping soybean can provide added value on a farming operation (Figure 1). This additional profit potential can also bring added risk, but the practice has become more common over the last several decades in the United States.
Double cropping, by definition, is harvesting two crops within the same year. Weed control is a critical component in double crop soybean given the shorter growing season, actively growing weeds, and potentially limited soil water availability. Some herbicides commonly used in early spring planted soybean, may not be available or the best option to use mid-summer.
When considering the herbicide program:
Include a timely application of product(s) that provide burndown and residual weed control.
Know which weeds are present in the field to select the best soybean trait and herbicide program options.
Early soybean growth and canopy coverage is critical to weed management. Herbicides that may burn soybean tissue and foliage should be avoided when possible.
Previous crop herbicide labels should be reviewed to determine there are no restrictions for double crop soybean.
Developing a solid herbicide program is a large piece of successful weed management in double crop soybean. Another piece to the puzzle revolves around sound agronomic and cultural practices.
Residue Management: Residue management of the prior crop is especially important during a hot and dry summer because surface residue can help conserve soil moisture, reduce soil temperature, and protect the soybean plants while reducing additional weed seed germination prior to soybean canopy (Figure 2).1
Seeding rate and row width: Narrowing row width and increasing seeding rate by 15 to 30% should be considered to help optimize sunlight capture from plants and increase the amount of potential seed set given the shortened growing period.2
Soybean maturity group: The maturity group of the soybean product is critical to achieve canopy coverage and provide enough time for the soybean plants to flower prior to senescence and/or frost.
1United Soybean Board. Double cropping beneficial to farmers. 2022. The Soy Hopper. https://www.unitedsoybean.org/hopper/double-cropping-beneficial-to-farmers/.
2Lofton, J., Zander, A., Leonard, K., and Harris, C. 2020. Management strategies for double-crop Soybean. PSS-2197. Oklahoma State University Extension. https://extension.okstate.edu/fact-sheets/management-strategies-for-double-crop-soybean.html/.\
Websites verified 3/15/23
ALWAYS READ AND FOLLOW PESTICIDE LABEL DIRECTIONS. Performance may vary, from location to location and from year to year, as local growing, soil and weather conditions may vary. Growers should evaluate data from multiple locations and years whenever possible and should consider the impacts of these conditions on the grower’s fields.
Channel® and the Arrow Design® and Seedsmanship At Work® are registered trademarks of Channel Bio, LLC. Bayer and Bayer Cross are registered trademarks of Bayer Group. All other trademarks are the property of their respective owners. ©2023 Bayer Group. All rights reserved.