The specific geography of individual wine growing regions has long been understood to be a significant factor in predicting both a region’s success in producing high quality grapes, and the resulting demand for wines produced from that region's fruit. In the American wine industry, American Viticultural Areas (AVAs) are increasingly being used to designate a uniqueness and specificity of place. This process is often predicated on the argument that these areas represent a certain degree of physiographic uniformity or homogeneity. This is particularly the case with regard to the phenomenon of sub-AVAs, wherein smaller areas within large, spatially heterogeneous AVAs seek to differentiate themselves based on the physiographic features that are purportedly unique to those smaller subregions. In many cases, there is a strong correlation between soil classes and AVA boundaries, whereas in other cases the correlation is not as strong. This suggests that there are factors other than physiographic homogeneity contributing to the designation of these sub-AVAs. This study employs GIS and spatial analysis to examine and potentially correlate the soil classes of Oregon's northern Willamette Valley with the sub-AVAs in that area. In doing so, this study presents maps and statistical results in order to provide a quantitative summary of the geographic context of vineyards in this region with respect to both the soil classes present and the federally designated AVA boundaries in which they are located.