Olympic National Forest Invasive Plant Program

Weeds Beware!

A series of workers in a field on a sunny day.

Photo: Treating Schmidts Knob with the WCC

The Olympic National Forest Invasive Plant Program typically begins annual control efforts in early May and continues into October. Treatments focus on high priority weed species, including herb Robert, Scotch broom, hawkweed, knotweed, tansy ragwort, and many more. 

A variety of control methods are used, including herbicides, but prevention is the most important element of any invasive plant control effort. We work hard to prevent the spread of noxious weeds through Forest activities. We appreciate your help in this effort! Here are some prevention measures you can take: 

  • Make sure the wheels on your vehicle and the shoes on your feet are free of dirt/mud and seeds  
  • Use only weed free straw  
  • Do not dump yard waste in the Forest  

Treated areas will be signed with a notice of treatment that will be posted for at least 30 days after the treatment. Herbicide treatments are done with a blue indicator that can be seen on as a blue hue on the ground in treated areas.  

The Forest works closely with several outside partners on the peninsula to complete this work. The success of our work on invasive plants would be impossible without them. Much appreciation to all our partners! 

Logos for the partners of the Invasive Plant Program

For more information about how you can help prevent invasive weeds from spreading, visit USFS Invasive Species.

Spiny green week with purple flowers shoots up from a green field on a sunny day in the mountains.

Photo: Canada thistle in the Buckhorn Wilderness 

EIS links:


Invasive Plant Program Staff:

Nick Jarvis
Invasive Plant Program Coordinator
(360) 956-2283

Cheryl Bartlett
Forest Botanist and Native Plant Program Coordinator
(360) 956-2283

Please contact us with questions