Weed management research in Maryland is conducted by weed scientists at both the University of Maryland and the Beltsville Agricultural Research Center of the USDA ARS in Beltsville, MD.

Maryland Weed Science Contacts:

Steven Mirsky – Research Ecologist, Head PI of the area-wide Integrated Weed Management program

Burkhard Schulz – Assistant Professor of Plant Science

Research on IWM in Maryland:

  • Cover Crop-based Weed Management (Beltsville)
  • An Integrated Pest Management Approach to Addressing the Multiple Herbicide-Resistant Weed Epidemic in U.S. Field Crop Production (Beltsville)
  • Herbicide Resistant Giant Ragweed – identifying the genes that make weeds resistant to glyphosate (UMD)
  • Organic Weed Control in No-Till Vegetable Systems (UMD) (click for more information)

Herbicide Resistant Weeds in Maryland

Updated October, 2016. Source: – Maryland

Reading this list: Each weed with herbicide resistant populations in this state is listed. Underneath each species is a list of the unique resistant biotypes of that weed in the state, according to the herbicide group(s) they are resistant to.

Palmer amaranth

  • Group 2 + Group 9


  • Group 9

Smooth pigweed

  • Group 5

Redroot pigweed

  • Group 2

Common lambsquarters

  • Group 5

Common ragweed

  • Glyphostate
  • ALS


  • Group 5


  • Group 5

Yellow foxtail

  • Group 5

Giant foxtail

  • Group 5

Italian ryegrass

  • Group 1 (ACCase inhibitors)

Common cocklebur

  • Group 2

Common chickweed

  • Group 2