Official Series Description


Lab Data Summary

Aggregate lab data for the POTOMAC soil series. This aggregation is based on all pedons with a current taxon name of POTOMAC, 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 POTOMAC were used in the calculation. Source: KSSL snapshot . Methods used to assemble the KSSL snapshot used by SoilWeb / SDE

There are insufficient data to create the lab data summary figure.


Water Balance

Monthly water balance estimated using a leaky-bucket style model for the POTOMAC 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.

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Sibling Summary

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

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

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Geomorphic description summaries for the POTOMAC 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 .

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Competing Series

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

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Select annual climate data summaries for the POTOMAC 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 POTOMAC 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 .

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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 POTOMAC, 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. KY-2012-02-01-38 | Pike County - June 1990

    Along the major tributaries in Pike County, the soils on the mountains are in the Marrowbone-Fedscreek-Kimper-Dekalb general soil map unit and those in the valleys are in the Yeager-Grigsby-Potomac-Hayter map unit (Soil Survey of Pike County, Kentucky; June 1990).

  2. KY-2012-02-01-39 | Pike County - June 1990

    Along Elkhorn Creek and Pine Mountain, the upper faulted mountains are in the Kimper-Sharondale-Berks-Shelocta general soil map unit, the lower mountains are in the Marrowbone-Fedscreek-Kimper-Dekalb map unit, and the valley is in the Yeager-Grigsby-Potomac-Hayter map unit (Soil Survey of Pike County, Kentucky; June 1990).

  3. WV-2012-03-23-01 | Boone County - June 1994

    Typical pattern of soils and parent material in the Dekalb-Pineville-Guyandotte general soil map unit (Soil Survey of Boone County, WV; 1994).

Map Units

Map units containing POTOMAC 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
Hayter-Potomac-Stokly complex, 2 to 15 percent slopesHpC13645550036lgc3ky19519861:24000
Potomac-Shelocta-Grigsby complex, 2 to 15 percent slopesPsC4387550876lh76ky63919911:24000
Potomac gravelly sandy loamPt126544100l85mpa03520021:24000
RiverwashRv2072540764l4q0pa04319671:15840
Potomac gravelly sandy loam, 0 to 3 percent slopes, extremely stony, frequently floodedPoA78729990372x4wtpa10519531:24000
RiverwashRv16214138931jg8gpa12119711:20000
Potomac gravelly loam, rarely floodedPo2242526481knv8tn01920001:24000
Philo stony fine sandy loam (Potomac cb-fsl)Ps832524542kltqtn02519481:24000
Potomac very cobbly loamy sand, 0 to 5 percent slopes, extremely bouldery, frequently floodedPo42553590ll1rtn64020071:24000
Potomac sandy loamPo1565514867k8rmwv00519881:24000
Atkins-Philo-Potomac complexAn5725553099lkjxwv02520021:24000
Tioga-Potomac complexTp2587553111lkk9wv02520021:24000
Potomac very gravelly fine sandy loamPt950553072lkj1wv02520021:24000
Potomac very cobbly fine sandy loamPt9209514201k824wv07119881:20000
Potomac fine sandy loamPo5923514200k823wv07119881:20000
Potomac very gravelly loamPt6362515435k9bywv07519921:24000
Potomac loamPo1804515434k9bxwv07519921:24000
Pope-Potomac complex, very cobblyPp3996515147k91nwv10119921:24000
Potomac-Urban land complex, 3 to 8 percent slopesPuB1665513506k7bqwv10919841:24000
Potomac sandy loam, 3 to 8 percent slopesPoB1125513505k7bpwv10919841:24000
Potomac-Nelse complex, 0 to 5 percent slopes, extremely stony, frequently floodedPxA47824851102pdyvwv62220101:12000
Combs-Potomac complex, 0 to 3 percent slopes, very stony, occasionally floodedCpA29324851132pdyywv62220101:12000
Potomac-Nelse complex, 0 to 5 percent slopes, extremely stony, frequently floodedPxA11324977572pdyvwv62320101:12000
Potomac fine sandy loamPb10102515955k9wqwv62819801:20000
Potomac cobbly loamPc8519515956k9wrwv62819801:20000

Map of Series Extent

Approximate geographic distribution of the POTOMAC 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 .