Early settlers drained marshy US landscape 19:00 17 January 2008 NewScientist.com news service Catherine Brahic A milldam on Pickering Creek in Chester County, Pennsylvania. The dam spans the entire valley, and is filled to the brim with sediment (Image: Robert Walter and Dorothy Merritts) Standard notions of the 'natural' eastern US landscape with its meandering ribbon-like streams may be misguided, suggests historical research. In the US, a multibillion-dollar landscape restoration industry is guided by the almost intuitive notion that natural, gravel-bedded streams wander in single channels across the land. This springs from the assumption that, when European settlers arrived in...