Nebraska

University of Nebraska Weed Science: http://weedscience.unl.edu/

Herbicide Resistant Weeds in Nebraska

Updated October 20, 2016. Source: John Lindquist, University of Nebraska; www.weedscience.org – Nebraska

Multiple-herbicide resistant weeds have been confirmed in Nebraska, including populations of Palmer amaranth that are resistant to both HPPD-inhibitor herbicides (Callisto, Laudis, etc) and triazines. Resistance to HPPD-inhibitors eliminates a key residual herbicide that is otherwise frequently recommended for Palmer amaranth control. Applicators and landowners in the area must be aware of the existence of these resistances in the state and avoid over-reliance on these modes of action, to help avoid the spread of these resistant populations. Please read: Multiple Herbicide Resistant Weeds and Challenges Ahead – Univ. of Nebraska CropWatch

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.

Tall waterhemp – Highest concern in eastern & south-central

  • Group 4
  • Group 5
  • Group 9
  • Group 27
  • Group 2

Palmer amaranth – Highest concern in eastern & south-central

  • Group 2
  • Group 5
  • Group 27
  • Group 5 + Group 27 (triazines, HPPD-inhibitors)
  • Group 5 + Group 9 (triazines, glyphosate)

Kochia – Highest concern in western NE

  • Group 4
  • Group 5
  • Group 9
  • Group 2
  • Group 2 + Group 9

Giant ragweed – Highest concern in northern & northeastern

  • Group 9

Common ragweed – Highest concern in northern & northeastern

  • Group 9

Horseweed/marestail

  • Group 9
  • Group 2

Johnsongrass

  • Group 2

Redroot pigweed

  • Group 5

Shattercane

  • Group 2