2023 Invasive Weed Treatment Services

In 2022, Kitsap County Noxious Weed Control Board terminated an interlocal agreement (ILA) with the City due to the vacancy of their Noxious Weed Control Program Coordinator. Under the ILA, Kitsap County was tasked with weed treatment services within the city boundaries. The City, in collaboration with the Bainbridge Island Cooperative Weed Management Area (CWMA), is seeking to supplement the gap in weed treatment services on the Island due to the termination of the ILA with Kitsap County to mitigate and control the spread of noxious weeds regulated by the State under Washington Administrative Code (WAC) Chapter 16-750.


City staff worked with the CWMA to identify the Waterfront Park and Lost Valley Trail sites as priority treatment areas, and the CWMA provided staff with recommendations for effective treatment of target noxious weed species, including Poison Hemlock and Japanese Knotweed. The proposed treatment methods include the use of non-glyphosate-based pesticides Triclopyr and Imazapyr for selective and non-selective treatment, respectively.


On April 5, 2023, staff issued an Invitation to Bid for 2023 Invasive Weed Treatment Services at the Lost Valley Trail and Waterfront Park sites. The proposed pesticides for effective treatment include, Imazapyr and Triclopyr, which are commonly used for treating noxious weeds in Kitsap County and have been used on Bainbridge Island by the Kitsap County Noxious Weed Control Program since before 2017.

On May 9, 2023, City Council authorized the immediate use of two low toxicity pesticides (herbicides), Triclopyr and Imazapyr, for the 2023 Invasive Weed Treatment Services contract.

On Monday, May 22, 2023, the City’s contractor will begin treatment (foliar spraying, injection, and cut-stem applications). The treatment areas will be closed to the public for 48-hours following the final treatment application, which is anticipated to be completed on May 23, 2023. This will allow time for the pesticides to dry, at which point the area will be safe for use.

Contact Us

  1. Matthew Oxford

    Project Manager
    Office: (206) 780-3709
    Cell: (206) 643-2610 

    Staff Directory


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