Soils in the Carleton undergraduate liberalarts curriculum

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Soils in the Carleton undergraduate liberal-arts
curriculum

• Mary Savina
• Department of Geology
• Carleton College

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Outline

• Students, liberal arts, and geology
• Geologic/Soils setting of Northfield
• labs and projects
• agriculture
• Geology Courses with soils content
• Evolution of Geology of Soils 1979-2001
• Comments, questions and discussion

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The liberal-arts tradition

• Broad education in arts, literature, science,
  humanities and social science
• Emphasis on broadly useful skills such as
  writing, foreign language, research (library and
  science)
• Little emphasis on practical applications
• No graduate programs, certificates, etc.
• (At Carleton) one degree B. A.

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Student profile

• Students from across the country
• Few students from rural backgrounds (most
  suburban)
• Fewer students from agricultural backgrounds
• Strong student interest in sciences

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Minnesota
Northfield is between the Twin Cities and
Rochester
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Soils and a Carleton sense of place

• Rice County - edge county, but still rural
• Most land cultivated
• Animal (dairy, hogs, poultry, beef, etc.) and
  crop (corn and soybeans) agriculture
• Students resident for four years

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Carleton history of agriculture - 1

• Carleton dairy farm 1914-1964
• Two courses in ag. science taught early on (not
  popular)
• Farmhouse used as student housing (Natural
  History house), 1971-present
• Organic garden - 1990s

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Carleton History of Agriculture - 2

• Renewed student interest in environment,
  agriculture starting in 1970s
• Courses now taught include Sustainable
  Agriculture (Bio.), The American Farm (Poli.
  Sci), Agriculture and the American Midwest (Eng.
  and Geo.), Population and Food in Global System
  (SOAN), Geology of Soils

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Geology at Carleton

• Courses taught since 1870s
• Department founded in 1933 by Laurence McKinley
  Gould (glacial and Quaternary geologist)
• Robert Ruhe, 42, Carleton graduate
• Average of 22 graduating seniors each year since
  1980
• Major requirements 7 geology courses, 2 math
  courses, chemistry and physics

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Minnesota
Eastern margin of Late Quaternary deposits passes
through Northfield.
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Soils in Southeastern Minnesota

• Young soils (lt14,000 yr. BP) on till and outwash
  on campus and west (little profile development)
• Older soils on loess till east and south of
  campus (few exposures)
• Prairie/Forest boundary
• Extensive wetlands
• Mollisols, Entisols, Alfisols, Histosols
• Cretaceous weathering (ultisols) in Mn. RV

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Borderlands

• Forest and lakes in recently glaciated terrain
• Prairie on bedrock and (much) older glacial
  material

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Factors of Soil Formation, SE Minnesota

• Parent material (Quaternary deposits, bedrock)
• Topography
• Vegetation (prairie, hardwood forest, wetland)
• Climate and time - Cretaceous, Early and Late
  Quaternary
• Human activity agriculture, forest clearance,
  urbanization, suburbanization

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Geology courses with soils content

• Introductory Geology (some versions)
• Introduction to Environmental Geology -
  stand-alone or as part of Agriculture and the
  American Midwest
• Geomorphology
• Oceans and Atmospheres
• Hydrology
• Geology of Soils

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Soils on Geology dept. field trips

• Northern Michigan - spodosols, paleosols
• SE and central Missouri - residual, cherty soils
  on limestone bedrock, paleosols
• Black Hills and Badlands, SD - sod table soils,
  carbonate accumulations, paleosols
• Baraboo, Wisconsin Northern Minnesota -
  Quaternary deposits

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My growing view of soils 1979-2001

• Soils as physical and mineralogical systems
• Soils as a subset of Quaternary geology and
  geomorphology
• Soils as indicators of past climates and time
  (paleoclimate and geochronologic reconstructions)
  
• Soils as the boundary between the lithosphere,
  atmosphere, hydrosphere and biosphere central
  to understanding global change

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Continuing education in soils

• Grad school - Soil Mechanics, Soil Mineralogy and
  Behavior courses
• Students - esp. Robb Jacobson, Richard Doyle
• Soils professionals on many field trips
• Pete Birkeland gets his own line
• Local soil resources people

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Carleton - Geology of Soils

• Taught since 1979, about every 2-3 years
• Enrollment range 12-36
• Prerequisite Introductory Geology
• Meets requirements for Geology Major,
  concentrations in Environmental and Technology
  Studies (ENTS) and Archaeology

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Two versions of Geology of Soils

• Texts - Singer and Munns Soils Birkeland, et
  al., Soils. . .Applied Quaternary Geology (Utah
  GMS) William Logan Bryant, Dirt The Ecstatic
  Skin of the Earth
• Emphasis - Soils as a biogeochemical system

• Text - Birkeland Soils and Geomorphology
• Emphasis - Weathering, pedogenesis, soils as
  chronological markers, soil mechanics

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Geology of Soils Purpose and Questions

• Goal understand soils as a complex
  biogeochemical system
• Q1 What are the observable characteristics of
  soils?
• Q2 How do soils get to be this way?
• Q3 Why are these characteristics important (for
  Quaternary geologists, environmental scientists,
  archaeologists)?

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Geology of Soils - Class Projects

• Soils mapping (and profile description) of parent
  material/topo sequence of Carleton Arboretum
• Use outcrops of Precambrian and Cretaceous of MN
  River Valley to repeat Goldichs weathering study
• Compare mollisols east and west of
  pedalfer/pedocal boundary
• Prairie/forest boundary
• Literature/bibliographic and final lab projects

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Main topics - Geology of Soils

• Soil profile description
• Factors of soil formation
• Soils mapping and suitability
• Weathering and pedogenesis
• Soil conservation agriculture
• Organic soils
• Soil classification
• Soils for Quaternary geology and archaeology

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Local sources of information and help

• Natural Resources Conservation Service (Tom
  Coffman)
• Rice County Soil and Water Conservation District
  (Theresa Weninger)

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Local sources of information and help

• University of Minnesota County Extension - Brad
  Carlson
• University of Minnesota Soils, Water and Climate
  - Gyles Randall, David Mulla, Steve Simmons

• University of Minnesota County Extension - Brad
  Carlson
• University of Minnesota Soils, Water and Climate,
  SROC - Gyles Randall, David Mulla, Steve Simmons
  (agronomy)

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Studying a Soil Profile
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Visiting farms
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Animal agriculture and soils
Jirik farm (above) Southern Research and Outreach
Station, UMN (right)
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Student final projects, 1999

• Do the soils in the prairie restoration areas of
  the arboretum exhibit significant differences in
  soil texture?
• Is the new proposed site for the Farm Club garden
  appropriate for tilling, etc? How does it
  compare to the old site?
• How has pine planting affected soil development
  in the lower arb?

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More student final projects

• What conservation practices are being used to
  control water erosion on Rice County farms and
  how effective are they?
• What are the possible land uses and land use
  restrictions imposed by soil properties near
  Blue, Texas?
• What are the soil differences between forest and
  restored prairie near Nerstrand?

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Conclusions

• A soils course at a place like Carleton can
• help students develop a sense of place in rural
  America
• give students a grounding in agricultural
  resources, both of the US and elsewhere
• be an integral part of a geology major
• link environmental science and global
  biogeochemistry courses

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Soils R Fun

• Pete Birkeland - CATENA supermarket
• Francis Holes Soil Songs
• Ian Smalley - Loess Inn
• William Bryant Logan - Dirt The Ecstatic Skin
  of the Earth