Wash. Rev. Code § 68.52.040
Any city or town may acquire, hold, or improve land for cemetery purposes, and may sell lots therein, and may provide by ordinance that a specified percentage of the proceeds therefrom be set aside and invested, and the income from the investment be used in the care of the lots, and may take and hold any property devised, bequeathed or given upon trust, and apply the income thereof for the improvement or embellishment of the cemeteries or the erection or preservation of structures, fences, or walks therein, or for the repair, preservation, erection, or renewal of any tomb, monument, gravestone, fence, railing, or other erection at or around a cemetery, lot, or plat, or for planting and cultivating trees, shrubs, flowers, or plants in or around the lot or plot, or for improving or embellishing the cemetery in any other manner or form consistent with the design and purpose of the city, according to the terms of the grant, devise, or bequest.
RCW 68.52.040