DESCRIPTION
The Pacific Conservation District used this grant to control Japanese knotweed, which was choking out native, riparian plants in the Naselle watershed. Riparian conditions within the Naselle watershed are deemed a high tier Limiting Factor. The Naselle watershed is a high tier watershed within the WRIA #24 Strategic Plan for Salmon Recovery.
Pacific Conservation District (PCD) staff and Pacific County Weed Management staff utilized an integrated pest management approach for controlling known infestations of knotweed within the Naselle watershed. Initial treatments applied a solution of 1.0 % imazapyr and 0.5% Dyne-Amic. The second and third year of treatment went with the same chemical solution and was implemented through a foliar application process. The PCD did not use the original chemical mixture because the use of glyphosate was not effective and actually reduced the percentage of control. Studies showed that using straight imazapyr was far more effective. We discussed this chemical solution with the Washington State Department of Agriculture Knotweed Coordinator and Pacific County Vegetation Management Director, all three entities felt this solution would be the most effective and least harmful to the existing habitat. In year three the CD worked with landowners in controlled areas to begin the replanting process. We are currently working on 4 CREP contracts but due to State and Federal budget cuts we are limited in the amount of native revegetation planting that can be done. Budget cuts have dramatically slowed down the replanting / revegetation process.
Both the Pacific County Weed Board and Pacific Conservation District have staff with Aquatic endorsement to a Washington State Public Operators Pesticide License. Licensed staff applied and worked under the NPDES permit, and followed all guidelines and requirements of the permit.
This project has and will continue to benefit all five salmonid species within the Naselle Watershed. After reclamation, other funding sources (CREP) will be utilized to revegatate the riparian buffers as federal and State budgets allow.