Soils Exam Two
How do we classify soils?
Land capability classes and by soils basic properties " Soil Taxonomy"
In soil taxonomy, which level is the broadest?
Which surface horizon is thick and dark colored with a chroma less then 3 and a high base saturation?
Mollic Epipedon (A)
Which surface horizon is thick and dark colored with a chroma value of 3 and a low base saturation?
Umbric Epipedon (A)
Which nutrient is an indicator of a mature profile?
Which soil horizon is light colored and has low organic content that may be hard and massive when dry? What is an example
Ochric (A) horizon - ex: Entisol
Which soil horizon is very high in O.M. and wet during part of the year (wetland)? The base saturation has to be ___% or higher.
Histic (O) horizon - 12% or higher
Which soil horizon is a man modified mollic horizon that has high available phosphorous (Europe) and higher O.M. due to irrigation. What are two locations in the world that contain this type of horizon due to long term animal production?
Anthropic (A) - The N.E. and Europe
Which soil horizon is man made sod-like that has lots of manure and is common in Europe?
Which soils are new/recent and have little profile development. Ochric epipedon is common (ENT)
Embryonic soils with few diagnostic horizons. Ochric or umbric epipedon, cambic horizon( young soil) (EPT) - Inception
Mollic epipedon, high base saturation, argillic or natric horizon. Mature/middle ages soils that form under high vegitative conditions (OLL)-Mollify
Pedalfer-argillic or natric horizon, medium to high base saturation. Middle aged soil that do not have the influence of O.M.-forms under forest applications (ALF)
Ultimate-argillic, low base saturation. They are older soils that have leached for a longer period of time. (ULT)
Oxide-Oxic horizon, no argillic, highly weathered. In topical soils such as TX, Hawaii, and GA. Really old soils not found in MS (OX)
Invert-high in swelling clays, deep cracks when soil is dry. (ERT)
Arid-Dry soil, ochric epipedon, sometimes argillic or natric horizon. Old soils with no moister and not found in MS (RID)
Podzol (Odd)-spodic horizon commonly Al or Fe and humus accumulation. Lots of reds and browns. Water management is hard. Found in MS and FL (OD)
Histology-peat or bog 12% O.M. or higher (IST)
Andesite- volcanic, dominated by allophane or Al humic complexes. Not in MS (AND)
Permafrost-Gelid. Not in MS (GEL)
Which soils are not found in MS?
Gelisols, Andisols, Oxisals, Aridisols
Based on genetic factors (Climatic, vegetation, wetness)
Based on the diagnostic horizons
Intergrades with soils of other orders
Based on texture, mineralogy, temperature, and soil depth.
Down the the pedon. generally named after a nearby town or location
Series (Most Specific)
based on pedon descriptions, define soil boundaries,compile soil information, communicate geographic information (Age, slope, ect..)
Whats does a soil survey description tell us?
Suitability for land use, chemical characteristics, physical characteristics, drainage, agricultural yield potential, non-agricultural potential