When people think of an unhealthy river, chemical discharges may be first thing that comes to mind, but other conditions in the water can also be a problem for fish and wildlife. The Oregon Department of Environmental Quality just released a 650-site assessment of the Willamette River basin which concludes in part that high water temperature is the basin’s biggest problem and adding native plant material to stream banks and riparian zones is the most cost-effective remedy, for sites in the city as well as the country. As reported by Scott Learn of The Oregonian (Portland, Ore.):

A thick tree canopy shades water, with fallen trees adding habitat for insects and fish. Thick vegetation helps stop and filter polluted runoff, whether it’s fertilizers from farms and city yards, oil from streets or sediment from logged land, said Aaron Borisenko, the laboratory’s watershed assessment manager. “It’s a strong statement that riparian condition is the thing to focus on to get bang for your buck,” Borisenko said. “It seems to be a fairly simple way of getting at some big problems.”

Back in June, Digger published an article (PDF) by Lisa Albert about the expanding market for native plants.