Official Series Description


Lab Data Summary

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

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Pedons used in the lab summary:

MLRALab IDPedon IDTaxonnameCINSSL / NASIS ReportsLink To SoilWeb GMap
14882P0479S1981MD027001Occoquan6Primary | Supplementary | Taxonomy | Pedon | Water Retention | Correlation | Andic Soil Properties39.2380667,-76.8628722
14886P0896S1986MD031004Occoquan7Primary | Supplementary | Taxonomy | Pedon | Water Retention | Correlation | Andic Soil Properties39.1734806,-77.051325

Water Balance

Monthly water balance estimated using a leaky-bucket style model for the OCCOQUAN 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 OCCOQUAN 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 OCCOQUAN 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 OCCOQUAN 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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There are insufficient data to create the 3D terrace figure.

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

Competing Series

Soil series competing with OCCOQUAN 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 OCCOQUAN series and competing. 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 OCCOQUAN 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 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 OCCOQUAN, 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. MD-2010-09-10-06 | Howard County - 2008

    Relationship of soils, topography, and underlying material in the Occoquan-Brinklow-Glenelg general soil map unit (Soil Survey of Howard County, Maryland; 2008).

  2. MD-2012-02-03-22 | Montgomery County - July 1995

    Typical pattern of soils in the Piedmont physiographic province in Montgomery County (Soil Survey of Montgomery County, Maryland; July 1995).

Map Units

Map units containing OCCOQUAN 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
Occoquan loam, 3 to 8 percent slopesOcB246559049lrqvmd02120011:12000
Occoquan loam, 8 to 15 percent slopesOcC11559048lrqtmd02120011:12000
Occoquan loam, 8 to 15 percent slopesOcC1546793446vmn1md02720041:12000
Occoquan loam, 3 to 8 percent slopesOcB883793445vmn0md02720041:12000
Occoquan loam, 3 to 8 percent slopes17B12005533583kx7cmd03119891:15840
Occoquan loam, 8 to 15 percent slopes17C5636533584kx7dmd03119891:15840
Occoquan loam, 25 to 50 percent slopes34E83881370534lm2va12519921:24000
Occoquan loam, 25 to 50 percent slopes, very stony35E72001370584lm7va12519921:24000
Occoquan loam, 15 to 25 percent slopes34D29531370524lm1va12519921:24000
Occoquan loam, 7 to 15 percent slopes34C7941370514lm0va12519921:24000
Occoquan loam, 15 to 25 percent slopes, very stony35D6871370574lm6va12519921:24000
Occoquan sandy loam, 7 to 25 percent slopes44D4664521203khc0va15319851:15840
Occoquan sandy loam, 25 to 50 percent slopes44E1187521204khc1va15319851:15840

Map of Series Extent

Approximate geographic distribution of the OCCOQUAN 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 .