Reed Canary grass is the nightmare of those who envision biological diversity in wetland areas. It is a large, coarse, and aggressive grass that spreads both by seed and underground root systems. It grows throughout the world, and there is not agreement whether it is 'native' to the Pacific Northwest or not. Irrespective of its origin, it spreads aggressively and establishes a monoculture particularly in wetlands that is devoid of most of the benefits that wetlands are touted for. It also grows in upland areas, and is common along roadsides. As livestock forage it is coarse and not favored by livestock but they will eat it and are likely the best form of control. In the usual scenario, visionaries will see low lying pasture land and envision envision a biologically diverse wetland if they could just get the cows off the pasture. To the extent they are successful in getting the livestock off the pasture, the area promptly turns into a Reed canary Grass monoculture which is usable by fewer other species than the pasture land was.
Ultimately, if they get started, and they usually do next comes the Himalayan blackberry and that is what you get. While it is difficult to understand how a combination of Himalayan blackberries and Reed canary grass is 'ecologically better' than cow pasture, it is the usual fate of wetlands restoration projects in the Pacific Northwest.