The Grande Ronde Sub-basin Invasive Weed Control project is a part of an ongoing mission carried out by Tri-County CWMA to protect and preserve all lands and resources in the tri-county area from degrading impacts of exotic, invasive, and noxious weeds.  This specific project targets leafy spurge (Euphorbia esula), meadow hawkweed (Hieracium pratense), and spotted knapweed (Centaurea maculosa) infestations within the Grande Ronde watershed.

Noxious weeds are infesting many areas throughout the Upper Grande Ronde Sub-basin and are threatening fish and wildlife habitat by contributing to increased sedimentation rates, diminishing riparian structure and function, and reducing forage quality and quantity.  These areas have been identified in range condition surveys done in the past by Tri-County CWMA and Union County Weed Management employees.  Targeted weeds in this project have been documented as A-listed weeds according to the Department of Agriculture rating system.  A-listed weeds are recognized as top priority for control measures and recommended action is eradication or intensive control when and where found.  Noxious weeds are identified as contributing factors to increased sedimentation in the Grande Ronde Sub-basin Plan (December 2004).   Tri-County CWMA works with Wallowa Resources, based out of Enterprise, Oregon, for seamless treatment of noxious weeds along the Upper and Lower Grande Ronde Watersheds.  Many other organizations recognize the importance of weed management within watershed corridors as well.  The Oregon Plan for Salmon and Watersheds (March 1997) identifies invasive species as indicators of endangered rangeland and water-basin health.  The Oregon Conservation Strategy (2006) lists the Upper Grande Ronde Sub-basin Weed Control Project’s entire target weed list as, “Invasive species currently considered to be the primary causes of species becoming threatened and endangered”.  The Upper Grande Ronde Sub-basin Noxious Weed Control Program addresses concerns and priorities of regional organizations to improve habitat for rangelands, riparian areas, and native fish populations.

Tri-County Cooperative Weed Management Area (CWMA) plans to survey and monitor vast areas of infested land for leafy spurge, spotted knapweed, and meadow hawkweed,.  Data will be collected within the Grande Ronde Watershed Basin, along the Grande Ronde River corridor, and adjoining stream drainages.  Integrated weed management control efforts will be defined and applied to improve habitat quantity, plant biodiversity, and reduce soil erosion and stream sedimentation.  Objectives are to:

*   Inventory and map high priority weeds,

*   coordinate treatment of those weeds,

*   release and monitor biocontrol agents,

*   educate the public as to the dangers of noxious weeds and how to deal with them,

*   and restore lands to productive plant communities after treatment.  

Tri-County CWMA will coordinate high priority weed treatment and restoration with all landowners and agencies throughout the program area. Tri-County CWMA will use other sources of funding to finance treatment activities.