Douglas County Weed Management

Welcome to the Douglas County Weed Management Website.

PLEASE NOTE:

The Pacific Northwest Weed Management Handbook, "Control of Problem Weeds" page has been updated!  This website give information regarding specific weeds that may be troublesome to control. Herbicides and/or rates listed cannot necessarily be used on cropland. Rates of application and restrictions vary depending on crop or site. Do not apply to a crop or site not listed on the label.

Control of Problem Weeds

In October 2004, Douglas County Commissioners activated the Douglas County Weed Management Task Force and appointed nine individuals who geographically represent Douglas County agriculture and urban areas. Margaret Viebrock, WSU Extension, was appointed to facilitate this committee and help to develop weed management strategies.

Ex-officio members of this Task Force include representatives from Douglas County Transportation and Land Services, Foster Creek Conservation District, Douglas County Commissioners and WSU Extension.

Task Force Directives (defined by the Douglas County Commissioners)

  • Develop a communication system with all entities that have weed control programs.
  • Gain a better understanding of weed control methods used by other other entities.
  • Design a system to coordinate weed control efforts.
  • Continue the process of developing an informed educational approach to weed management in Douglas County.
  • Engage landowners and agencies in a cooperative weed management program.

 

Since the appointment of the Douglas County Weed Management Task Force, the committee has taken a proactive approach to learn about various weed management programs. Members have met with agency people, integrated weed management program managers, state weed board representatives, county noxious weed control managers and other groups who manage weeds. The best parts of these programs have been integrated into the local plan of work. Members have also spent time in Olympia with state legislative groups explaining how the program has been successful in Douglas County.

WEED OF THE MONTH

Russian Knapweed

Russian Knapweed Flowers

Russian Knapweed Infestation

Russian Knapweed Facts

  • Douglas County Class B weed.
  • Native to Russia and Eastern Europe
  • Flowers: pink to purple. The outer bracts under the flower heads are greenish to straw colored and have a broad, papery tip.
  • Bushy, branched perennial, usually 1 to 3 feet tall.
  • It can also form clones or colonies from vigorous, deep, spreading rhizomes.
  • Russian knapweed can be found growing in pastures, hayfields, grain fields, irrigation ditches as well as roadsides.
  • Russian knapweed reproduces by seed and spreads laterally by its root system. Root fragments can regenerate following cultivation.
  • Other names: hardheads, Turkestan thistle
  • Control Methods:

How do I control it?

Prevention: Prevent establishment by managing to minimize disturbance. Clean machinery, vehicles, and equipment of attached plants.

Cultural Control: Depending on the moisture regime, nitrogen fertilizer applied in conjunction with an herbicide significantly improves the competitiveness of residual grasses. In addition, improved grazing management will significantly influence the life span of Russian knapweed control efforts.

Biological Control: The gall midge Jaapiella ivannikovi forms galls on Russian knapweed that reduce plant vigor but not kill the plant.

Herbicide Control: Milestone (Aminopyralid) works well on Russian knapweed. Please refer to the PNW Weed Management Handbook, or contact your county noxious weed coordinator for additional chemical options.