Washington

Washington State University Weed Science contacts: http://css.wsu.edu/research/weed-science/

Washington State University Weed Identification: http://css.wsu.edu/extension/weed-identification/

Herbicide resistant weeds in Washington

Updated November, 2016. Source: www.weedscience.org – Washington, Rick Boydston, Ian Burke

Reading this list: Under each species is a list of the unique resistant populations in the state, according to the herbicide group they are resistant to.

Prickly lettuce

  • Group 2
  • Group 4

Common groundsel

  • Group 5

Russian thistle

  • Group 2

Yellow starthistle

  • Group 4

Kochia

  • Group 2

Wild oat

  • Group 1

Powell amaranth

  • Group 5

Spiny sowthistle

  • Group 2

Redroot pigweed

  • Group 5

Lambsquarters

  • Group 5

Mayweed chamomile

  • Group 2