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ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Sustainable Agricultural Systems Laboratory » Research » Publications at this Location » Publication #425909
Research Project: Developing, Evaluating, and Optimizing Diversified Agricultural Systems for a Changing Environment in the Mid-Atlantic Region

Location: Sustainable Agricultural Systems Laboratory

Title: Evaluating seed impact mill efficacy during commercial soybean and wheat harvest

Author
item RUSSELL, ELI - Virginia Tech
item BAMBER, KEVIN - Virginia Tech
item CHU, SARAH - Texas A&M University
item BAGAVATHIANNAN, MUTHUKUMAR - Texas A&M University
item Mirsky, Steven
item BELJERI, KRESHNIK - Collaborator
item LAW, EUGENE - The Ohio State University
item CRANE, WALKER - Collaborator
item SCOTT, BARBARA - University Of Delaware
item VANGESSEL, MARK - University Of Delaware
item FLESSNER, MICHAEL - Virginia Tech

Submitted to: Crop and Pasture Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/24/2026
Publication Date: 4/27/2026
Citation: Russell, E.C., Bamber, K.W., Chu, S.A., Bagavathiannan, M.V., Mirsky, S.B., Beljeri, K., Law, E.P., Crane, W., Scott, B., Vangessel, M.J., Flessner, M.L. 2026. Evaluating seed impact mill efficacy during commercial soybean and wheat harvest. Crop and Pasture Science. 77(4). Article eCP25095. https://doi.org/10.1071/CP25095.
DOI: https://doi.org/10.1071/CP25095

Interpretive Summary: Weed control is a critical agricultural task. One non-chemical way to cut down on weed populations is to kill seeds remaining on parent weed plants at cash crop harvest, to prevent the seeds from reaching the soil (i.e. Harvest Weed Seed Control). Seed impact mills are aftermarket modifications mounted to the back of a harvest combine that crush weed seeds as the chaff (cash crop and weed debris) leaves the combine. This study evaluated two seed impact mills, the integrated Harrington Seed Destructor (iHSD) in soybean and the Redekop Seed Control Unit (SCU) in soybean and wheat, for effectiveness at killing weed seeds. The impact mills killed more than 98% of seeds of all tested species during soybean harvest. During wheat harvest, seed kill was greater than 91% for annual ryegrass and greater than 99% for rapeseed and hairy vetch. This research demonstrates that farmers needing to reduce the return of problematic weed species' seeds to the soil seedbank would benefit from the use of an impact mill as part of a weed management program.

Technical Abstract: Context: Harvest weed seed control (HWSC) targets weed seeds as they pass through the harvester. Seed impact mills are aftermarket modifications that are mounted onto the back of the harvester and are one way to implement HWSC. These mills process the chaff fraction as it exits the harvester and kills the weed seeds therein. Aims: Two experiments were conducted to evaluate the integrated Harrington Seed Destructor (iHSD) in soybean and the Redekop Seed Control Unit (SCU) in soybean and wheat. The purpose was to determine weed seed kill by the mill (weed seed kill) and seed loss in the straw (weed seed fate) during commercial harvest. Methods: During harvest, a known amount of weed seeds was fed into the harvester front or directly into the mill and captured in the chaff or straw of harvester outputs. Six weed species were tested in soybean with the iHSD, and three species each were tested in soybean and wheat with the SCU. Key results: The mills delivered >98% seed kill on all tested species during soybean harvest. In wheat, seed kill was >91% for Italian ryegrass and >99% for the other two species tested. During soybean and wheat harvest, <7% of seeds escaped HWSC in the straw fraction. Conclusions: These data indicate that both mills generate high seed kill during grain crop harvest and very few seeds escape HWSC in the straw fraction. Implications: Seed impact mills could be used during harvest to reduce the return of problematic species to the soil seedbank.