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What is a Soil Series?. CSES 4844 and 5244 Soil Interpretation Using GIS and DSS 1/29/2006. Hierarchy of Soil Taxonomy. Eliminatory, 6-level, top-down heirarchy system. Starts at top with order, suborder, great group, subgroup, family, and SERIES.
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What is a Soil Series? CSES 4844 and 5244 Soil Interpretation Using GIS and DSS 1/29/2006
Hierarchy of Soil Taxonomy • Eliminatory, 6-level, top-down heirarchy system. • Starts at top with order, suborder, great group, subgroup, family, and SERIES. • There are keys at all levels except the SERIES level and the Phase level. • Soil series cannot have ranges that fall entirely outside of the classes at the levels above them in Soil Taxonomy. For example, if the soil is fine-loamy particle size, the range of rock fragments cannot have a minimum of 40%. • The PHASE level is used to name the specific properties within the range of the SERIES properties that apply to a specific map unit in a legend in a soil survey.
Soil Series • In the opening paragraph, called the thumbnail sketch or simple description, some information is very specific. For example, classification to family level, depth and drainage class, average rainfall and temperatures, parent material type (ex: residuum), permeability of the subsoil. • In other parts of the opening paragraph, they provide a broad range of properties. For example, states located in, Rock types included in the parent material (ex: sandstone to shale), elevation range, slope ranges, and flooding frequencies. • In the Range in Characteristics section, colors of the subsoil, reaction classes (pH), presence or absence of horizons, textures and clay content allowed, rock fragment content, and thickness of horizons are all given as broad ranges.
Phases of Soil Series • Used to identify specific properties in the Map Unit Legend name, and these are specific to that map unit. The properties are within the series range but are much narrower than the full series ranges. • Examples are surface texture, a narrow slope range, erosion class (optional), and flooding frequency. See National Soil Survey Handbook at the NRCS soils web site for more details. • Phase names are not all used for each map unit type. See full discussion of the Map Unit Legend and types of map units and components. • Sometimes a special list of phases is also mentioned in the name. In some cases, phases are set up to identify why a soil falls outside of the soil series range. This is used when there is no other soil series that describes that range. For example, a saline surface phase identifies a soil that is very similar to the named soil series but has higher salinity than allowed by the series, and must be managed differently. In addition, no such saline soil series exists.
Where to Find Information? http://soils.usda.gov - The Main Source Official Soil Series Descriptions link in the left-hand frame.http://soils.usda.gov/technical/classification/osd/index.html National Soil Survey Handbook - http://soils.usda.gov/technical/ Soil Survey Manual - http://soils.usda.gov/technical/
An Example of an OSD LOCATION KELLY VA+MD Established SeriesRev. JHS-MAV01/2006 KELLY SERIES The Kelly series consists of deep, somewhat poorly drained soils formed in residuum that weathered from gray to brown hornfel and granulite on upland flats and sideslopes in the Culpeper Basin. Permeability is slow or very slow. Slopes range from 0 to 10 percent. Mean annual precipitation is about 40 inches and mean annual temperature is about 54 degrees F. TAXONOMIC CLASS: Fine, vermiculitic, mesic Aquic Hapludalfs
TYPICAL PEDON Description TYPICAL PEDON: Kelly silt loam on a south facing slope in pasture at 335 feet elevation. • Next page for details
A--0 to 5 inches; grayish brown (2.5Y 5/2), silt loam; weak coarse granular structure; very friable, slightly sticky, slightly plastic; common fine, medium, and coarse roots; common fine moderate continuity tubular pores; few fine prominent irregular yellowish red (5YR 4/6), moist, iron-manganese masses with diffuse boundaries; extremely acid; clear smooth boundary. • Bt1--5 to 13 inches; light yellowish brown (2.5Y 6/3), silty clay loam; moderate coarse angular blocky structure; friable, slightly sticky, slightly plastic; few fine roots and common medium, coarse, and very coarse roots; common fine moderate continuity tubular pores; patchy distinct light yellowish brown (2.5Y 6/3), moist, clay films on all faces of peds and discontinuous distinct light yellowish brown (2.5Y 6/3), moist, clay films on surfaces along pores; many medium distinct irregular yellowish brown (10YR 5/4), moist, iron-manganese masses with diffuse boundaries; very strongly acid; gradual smooth boundary. • Bt2--13 to 21 inches; dark yellowish brown (10YR 4/6), clay; weak coarse angular blocky structure; firm, slightly sticky, moderately plastic; few fine and medium roots; common medium moderate continuity tubular pores; discontinuous distinct dark yellowish brown (10YR 4/6), moist, clay films on all faces of peds; common medium prominent irregular light gray (10YR 7/1), moist, iron depletions with diffuse boundaries and common medium distinct irregular yellowish brown (10YR 5/6), moist, iron-manganese masses with diffuse boundaries; strongly acid; diffuse wavy boundary. • Bt3--21 to 37 inches; dark yellowish brown (10YR 4/6), clay; weak very coarse subangular blocky structure; firm, moderately sticky, moderately plastic; few fine roots throughout; patchy prominent dark yellowish brown (10YR 4/6), moist, slickensides on all faces of peds and discontinuous distinct dark yellowish brown (10YR 4/6), moist, clay films on all faces of peds; many medium prominent irregular gray (10YR 6/1), moist, iron depletions with diffuse boundaries; strongly acid; clear smooth boundary. • BC--37 to 42 inches; white (5Y 8/1), brown (7.5YR 5/2), and yellowish brown (10YR 5/6), silty clay; massive; friable, slightly sticky, slightly plastic; few fine roots; strongly acid; abrupt smooth boundary. • C--42 to 46 inches; brown (7.5YR 5/2), silt loam; massive; friable, nonsticky, nonplastic; few fine roots; moderately acid; very abrupt smooth boundary. • R--46 inches; hard brown (7.5YR 5/2) hornfel bedrock.
TYPE LOCATION: Culpeper County, Virginia. From Mitchells, 1200 feet northeast, then 1800 feet east-southeast, on Route 652. Site is 250 southwest in an abandoned pasture. USGS Culpeper West topographic quadrangle. lat. 38 degrees 22 minutes 37.16 seconds N. and long. 78 degrees 1 minutes 12.41 seconds W. • RANGE IN CHARACTERISTICS: The depth of solum ranges from 24 to 48 inches, argillic thickness ranges from 13 to 42 inches, and depth to hard bedrock ranges from 40 to 60 inches. Hornfel and granulite gravel content range from 0 to 30 percent in the A and B horizons and from 0 to 40 percent in the BC and C horizons. Cobbles or flagstones of hornfel or granulite make up 0 to 5 percent of the C horizon. • The A horizon has hue of 10YR, 2.5Y or neutral, value of 3 to 5 and chroma of 0 to 3. It is loam, silt loam or silty clay loam. Reaction is extremely acid to moderately acid. • Some pedons have an Ap horizon. It has hue of 10YR, 2.5Y or neutral, value of 2 to 5 and chroma of 0 to 4. It is loam, silt loam or silty clay loam. Reaction is extremely acid to moderately acid.
GEOGRAPHIC SETTING: Kelly soils formed in residuum weathered from gray to brown hornfel and granulite and are on level to gently sloping uplands of the Culpeper basin in the northern Piedmont Plateau. Slopes range from 0 to 10 percent. Mean annual temperature ranges from 53 to 57 degrees F., and mean annual precipitation ranges from 38 to 45 inches, frost free days range from 165 to 203, and elevation ranges from 200 feet to 600 feet above sea level. • GEOGRAPHICALLY ASSOCIATED SOILS: These are the Albano, Catlett, Ott, and Sycoline soils. Albano soils are in concave landscape positions and are poorly drained. Ott and Sycoline soils are on similar landscape positions. Ott soils are moderately deep and well drained. Sycoline soils are moderately deep and moderately well drained. Catlett soils are on steeper side slopes and are shallow and well drained.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained. The potential for surface runoff is low to medium. Permeability is slow or very slow. In undisturbed areas, the depth to the top of the seasonal high water table ranges from 10 to 20 inches for some time in most years. • USE AND VEGETATION: Cleared areas are used for corn, wheat, pasture and hay. About 40 percent of the area is in native forest of oaks, hickory, ash, and Virginia pine. • DISTRIBUTION AND EXTENT: Culpeper basin in Virginia and Maryland, possibly the southern end of the Gettysburg basin of Maryland. The series is of moderate extent.
REMARKS:1. Classification and type location changed to Prince William County, Virginia 1981. Type location moved back to Culpeper County, Virginia in 2003. On the 1986 OSD, authors were RSW, JHE, and DDR. RRD changed it to ACB, RRD in 1997. This 2003 revision by JHS-MAV removed statements about forming partly in periglacially transported materials. • 2. Diagnostic horizons and features recognized in this pedon are: a. Ochric epipedon - the zone from 0 to 5 inches (A horizon).b. Argillic horizon - the zone from 5 to 37 inches (Bt horizons).c. Lithic contact - at 47 inches (R horizon). • ADDITIONAL DATA: Lab date is available. Kelly soils normally have high amounts of exchangeable Mg, and Mg to Ca rations of greater than 1:1. Magnesium toxicity may be a limiting factor in use and management of these soils.