Official Series Description


Lab Data Summary

Aggregate lab data for the WILLAMETTE soil series. This aggregation is based on all pedons with a current taxon name of WILLAMETTE, and applied along 1-cm thick depth slices. Solid lines are the slice-wise median, bounded on either side by the interval defined by the slice-wise 5th and 95th percentiles. The median is the value that splits the data in half. Five percent of the data are less than the 5th percentile, and five percent of the data are greater than the 95th percentile. Values along the right hand side y-axis describe the proportion of pedon data that contribute to aggregate values at this depth. For example, a value of "90%" at 25cm means that 90% of the pedons correlated to WILLAMETTE were used in the calculation. Source: KSSL snapshot . Methods used to assemble the KSSL snapshot used by SoilWeb / SDE

Click the image to view it full size.

Pedons used in the lab summary:

MLRALab IDPedon IDTaxonnameCINSSL / NASIS ReportsLink To SoilWeb GMap
291P074891OR047002Willamette5Primary | Supplementary | Taxonomy | Pedon | Water Retention | Correlation | Andic Soil Properties45.0416679,-122.9416656
240A0943S1959OR043001Willamette5Primary | Supplementary | Taxonomy | Pedon | Water Retention | Correlation | Andic Soil Properties44.4742508,-123.1597977
240A0944S1959OR043002Willamette5Primary | Supplementary | Taxonomy | Pedon | Water Retention | Correlation | Andic Soil Properties44.4449997,-123.1811142
240A0945S1959OR043003Willamette5Primary | Supplementary | Taxonomy | Pedon | Water Retention | Correlation | Andic Soil Properties44.4449997,-123.1811142
292P0765S1992OR003002WILLAMETTE7Primary | Supplementary | Taxonomy | Pedon | Water Retention | Correlation | Andic Soil Properties44.4336128,-123.2719421
209N0802S2008OR071001Willamette7Primary | Supplementary | Taxonomy | Pedon | Water Retention | Correlation | Andic Soil Properties45.2247772,-123.2312241
213N0420S2012OR003002Willamette7Primary | Supplementary | Taxonomy | Pedon | Water Retention | Correlation | Andic Soil Properties44.625984,-123.217303

Water Balance

Monthly water balance estimated using a leaky-bucket style model for the WILLAMETTE soil series. Monthly precipitation (PPT) and potential evapotranspiration (PET) have been estimated from the 50th percentile of gridded values (PRISM 1981-2010) overlapping with the extent of SSURGO map units containing each series as a major component. Monthly PET values were estimated using the method of Thornthwaite (1948). These (and other) climatic parameters are calculated with each SSURGO refresh and provided by the fetchOSD function of the soilDB package. Representative water storage values (“AWC” in the figures) were derived from SSURGO by taking the 50th percentile of profile-total water storage (sum[awc_r * horizon thickness]) for each soil series. Note that this representation of “water storage” is based on the average ability of most plants to extract soil water between 15 bar (“permanent wilting point”) and 1/3 bar (“field capacity”) matric potential. Soil moisture state can be roughly interpreted as “dry” when storage is depleted, “moist” when storage is between 0mm and AWC, and “wet” when there is a surplus. Clearly there are a lot of assumptions baked into this kind of monthly water balance. This is still a work in progress.

Click the image to view it full size.



Click the image to view it full size.

Sibling Summary

Siblings are those soil series that occur together in map units, in this case with the WILLAMETTE series. Sketches are arranged according to their subgroup-level taxonomic structure. Source: SSURGO snapshot , parsed OSD records and snapshot of SC database .

Click the image to view it full size.

Select annual climate data summaries for the WILLAMETTE series and siblings. Series are sorted according to hierarchical clustering of median values. Source: SSURGO map unit geometry and 1981-2010, 800m PRISM data .

Click the image to view it full size.

Geomorphic description summaries for the WILLAMETTE series and siblings. Series are sorted according to hierarchical clustering of proportions and relative hydrologic position within an idealized landform (e.g. top to bottom). Most soil series (SSURGO components) are associated with a hillslope position and one or more landform-specific positions: hills, mountain slopes, terraces, and/or flats. Proportions can be interpreted as an aggregate representation of geomorphic membership. The values printed to the left (number of component records) and right (Shannon entropy) of stacked bars can be used to judge the reliability of trends. Small Shannon entropy values suggest relatively consistent geomorphic association, while larger values suggest lack thereof. Source: SSURGO component records .

There are insufficient data to create the 2D hillslope position figure.

There are insufficient data to create the 3D hills figure.

There are insufficient data to create the 3D mountains figure.

Click the image to view it full size.

There are insufficient data to create the 3D flats position figure.

Competing Series

Soil series competing with WILLAMETTE share the same family level classification in Soil Taxonomy. Source: parsed OSD records and snapshot of the SC database .

Click the image to view it full size.

Select annual climate data summaries for the WILLAMETTE series and competing. Series are sorted according to hierarchical clustering of median values. Source: SSURGO map unit geometry and 1981-2010, 800m PRISM data .

Click the image to view it full size.

Geomorphic description summaries for the WILLAMETTE series and competing. Series are sorted according to hierarchical clustering of proportions and relative hydrologic position within an idealized landform (e.g. top to bottom). Proportions can be interpreted as an aggregate representation of geomorphic membership. Most soil series (SSURGO components) are associated with a hillslope position and one or more landform-specific positions: hills, mountain slopes, terraces, and/or flats. The values printed to the left (number of component records) and right (Shannon entropy) of stacked bars can be used to judge the reliability of trends. Shannon entropy values close to 0 represent soil series with relatively consistent geomorphic association, while values close to 1 suggest lack thereof. Source: SSURGO component records .

There are insufficient data to create the 2D hillslope position figure.

There are insufficient data to create the 3D hills figure.

There are insufficient data to create the 3D mountains figure.

There are insufficient data to create the 3D terrace figure.

There are insufficient data to create the 3D flats position figure.

Soil series sharing subgroup-level classification with WILLAMETTE, arranged according to family differentiae. Hovering over a series name will print full classification and a small sketch from the OSD. Source: snapshot of SC database .

Block Diagrams

Click a link below to display the diagram. Note that these diagrams may be from multiple survey areas.

  1. OR-2012-05-10-21 | Yamhill County - January 1974

    Pattern of typical soils of association 4 on recent alluvial bottom lands, flood plains, and terraces of the Willamette Valley (Soil Survey of Yamhill County, Oregon; January 1974).

Map Units

Map units containing WILLAMETTE as a major component. Limited to 250 records.

Map Unit Name Symbol Map Unit Area (ac) Map Unit Key National Map Unit Symbol Soil Survey Area Publication Date Map Scale
Willamette silt loam, 0 to 3 percent slopes1693178854072vw2or00320041:24000
Willamette silt loam, 3 to 12 percent slopes1703071854082vw3or00320041:24000
Willamette silt loam, 12 to 20 percent slopes17133854542vxlor00320041:24000
Willamette silt loam, 0 to 3 percent slopes75A32606243322yzor05319771:20000
Willamette silt loam, 3 to 12 percent slopes75C18726243422z0or05319771:20000
Willamette silt loam, 12 to 20 percent slopes75D1136243522z1or05319771:20000
Willamette silt loam, 0 to 3 percent slopes44A3957615082204or06719751:20000
Willamette silt loam, 3 to 7 percent slopes44B1360615092205or06719751:20000
Willamette silt loam, 7 to 12 percent slopes44C216615102206or06719751:20000
Willamette silt loam, 12 to 20 percent slopes44D196615112207or06719751:20000
Willamette silt loam, 3 to 12 percent slopes2309C5827111052lkh0or06719751:20000
Willamette silt loam, 0 to 3 percent slopes2309A450427112882lkgzor07119671:24000
Willamette silt loam, 3 to 12 percent slopes2309C87727113762lkh0or07119671:24000
Willamette silt loam, 12 to 20 percent slopes2309D20527114072lkh1or07119671:24000
Willamette silt loam, wet, 0 to 3 percent slopes88A148561743227qor61019821:20000
Willamette silt loam, 0 to 3 percent slopes86A122561739227lor61019821:20000
Willamette silt loam, gravelly substratum, 0 to 3 percent slopes87A121561742227por61019821:20000
Willamette silt loam, wet, 3 to 7 percent slopes88B117261744227ror61019821:20000
Willamette silt loam, 3 to 8 percent slopes86B80161740227mor61019821:20000
Willamette silt loam, 8 to 15 percent slopes86C32561741227nor61019821:20000
Willamette silt loam10271256425024vlor63919831:20000
Willamette silt loam, 0 to 3 percent slopesWlA76866417024s0or64319661:20000
Willamette silt loam, 3 to 12 percent slopesWlC16666417124s1or64319661:20000

Map of Series Extent

Approximate geographic distribution of the WILLAMETTE soil series. To learn more about how this distribution was mapped, or to compare this soil series extent to others, use the Series Extent Explorer (SEE) application. Source: generalization of SSURGO geometry .