Best Management Practices for the Agronomic Grower

  • Plant only clean crop seed that is certified. State seed laws prevent crop seed contamination.
  • Use integrated management practices to aggressively control weeds. For example, decreasing row widths results in faster canopy closure and shade formation. Palmer Amaranth does not survive well under dense crop canopies as seeds require light to germinate.
  • Manage infested fields with no-till if possible, leaving any potential seeds near the soil surface.
  • Use residual herbicides (pre and post) during the growing season to prevent new flushes.
  • Apply effective herbicides to small plants that are less than four inches tall. It’s critical that you use the full recommended rate of application. Closely monitor fields before and after herbicide application.
  • With smaller infestations, physically remove plants. Pull by hand or use a hoe. Remove plants from field so they do not re-root. Bag and bury or burn removed plants along the field’s edge.
  • Plant corn or a perennial forage instead of soybeans in fields that are known to be infested. This provides more options for effective herbicides or alternatives for mowing and mechanical control.
  • Do not combine harvest mature pigweeds. If combine harvest cannot be avoided, harvest infested fields last to avoid moving seeds away from the infested fields.
  • Clean tillage and harvest equipment before leaving infested fields.
  • Ensure that used equipment, custom machinery, imported feed or hay, imported manure and compost are not contaminated with noxious pigweed.
  • Monitor field edges, ditches and fencerows for noxious pigweed plants. It’s important to scout after harvest, especially after silage harvest.
  • Aggressively control plants to prevent seed production and spread.

Download Publication

Article Details


Best Management Practices for the Agronomic Grower

This publication is available in alternative media on request.

Contact Information

William S. Curran
  • Professor of Weed Science
Phone: 814-863-1014