Soil survey. Web Soil Survey (US Natural Resources Conservation Service) You may search for your area of interest via an interactive map, then display the soil map and soil type characteristics. A paper copy of the Soil Survey for Multnomah County (OR) is available in the UO Libraries’ Document Center (DOC-LC S599.O7 G727 1983).
Surf Your Watershed (EPA): data for the Lower Willamette Watershed
Agriculture. Census of Agriculture 2007
County level data for Oregon.Click by table title for specific crops, look for Multnomah County.