Settlers found riparian forests, also called gallery or bottomland forests, growing abundantly on the floodplains of the Willamette River and its tributaries. These forests included a diverse mosaic of brushy thickets, marshes, and ash openings, maintained through annual inundation by floods. On average, these forests were one to two miles wide, but reached up to seven miles in width at the confluence of the Willamette and Santiam Rivers.
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