The Walla Walla County Conservation District conducted a 3 year project to remove Japanese Knotweed (Fallopia japonicus) and Bohemian Knotweed (Fallopia japonicus x bohemica) from 5.65 mi of Mill Creek and other isolated patches within Walla Walla County. The first year was concerned with locating, marking and spraying all marked plants. The second year was spent monitoring & treating any plants that survived the first spraying. The third year was used to continue to monitor this reach after treatment and to spray any newly found plants. The goal of this project was to restore a native riparian zone for the benefit of Chinook salmon and steelhead trout. The introduction of this plant has been the cause for great concern for riparian habitat function. This big, very invasive plant species is capable of completely dominating the entire riparian zone, thus eliminating most if not all of the native plant species diversity along creeks such as Mill Creek. Prior to treatment, the infestation was at a low level yet spreading. This highly invasive plant populated the riparian areas and had started to colonize the primary stream channel of Mill Creek upstream from Seven Mile Bridge in southeastern Walla Walla County. Within the stream channel, the plant can block flows, spread rhizomes and seeds downstream, and potentially block fish passage if allowed to expand. This project was run through the Walla Walla County Weed Board in compliance with the Washington State Dept. of Ag knotweed removal protocols.