Wash. Rev. Code § 17.04.210
The weed inspector shall keep an accurate account of expenses incurred by him or her in carrying out the provisions of this chapter with respect to each parcel of land entered upon, and the prosecuting attorney of the county or the attorney for the weed district shall cause to be served, mailed, or posted in the same manner as provided in this chapter for giving notice to destroy noxious weeds, a statement of such expenses, including description of the land, verified by oath of the weed inspector to the owner, lessee, mortgagee, occupant or agent, or person having charge of said land, and coupled with such statement shall be a notice subscribed by said prosecuting attorney or attorney for the weed district and naming a time and place when and where such matter will be brought before the board of directors of such district for hearing and determination, said statement or notice to be served, mailed, or posted, as the case may be, at least ten days before the time for such hearing.
RCW 17.04.210