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Soils References for the Alaska Envirothon

Soils References for the Alaska Envirothon

Soil Study Material

Soil Characterization Protocols

Careers in Soil Science

Glossary of Soil Science Terms, from the Soil Science Society of America

Soil pH: What it means, from State University of New York College of Environmental Science and Forestry

These documents require
Adobe Acrobat:

From the Surface Down - An Introduction to Soil Surveys for Agronomic Use 

Determining Soil Texture by the Feel Method, from Kansas State University

Key to Soil Taxonomy

Soil Erosion from NRCS USDA 

Understanding Soil Risks and Hazards from NRCS USDA 

Soil Survey of Upper Tanana Area, Alaska 


Introductory Presentation
Illustration, Charts, and Tables


For an Envirothon, it is important to be familiar with how to use a clinometer to measure slope, a topographic map to measure relief
and write legal descriptions.  It is also necessary to understand a Munsell color book, a textural triangle, and a soil survey.


Legal descriptions:
The primary purpose of a legal description (title description) is to describe a particular parcel of land in a way that uniquely describes only the subject parcel, without ambiguity. In the United States, the most common methods used to describe land are by reference to a lot, by the township and range system, by metes and bounds, or by a combination of these. Township and Range System descriptions are legal descriptions using the nomenclature of the U.S. Public Land Survey System. This would include references to portions of Sections, Townships, and Ranges. Land within rural or undeveloped land is often described this way. A typical legal description of this nature would read something like "The northwest quarter of the southwest quarter of Section 30, Township 1 North, Range 70 West of the Sixth Principal Meridian" (a portion of downtown Boulder). Each occurrence of the word "quarter" indicates the division of the section (roughly one mile square) into quadrants (quarters), with each quarter being progressively divided into further quarters.


Terms used in the Township and Range System:
Section: Basic unit of the system, a square tract of line one mile by one mile containing 640 acres.

Township: 36 sections arranged in a 6 by 6 array, measuring 6 miles by 6 miles. Sections are numbered beginning with the northeast-most section, proceeding west to 6, then south along the west edge of the township and to the east.

Range: Assigned to a township by measuring east or west of a Principal Meridian

Range Lines: North to south lines which mark township boundaries

Township Lines: East to west lines which mark township boundaries

Principal Meridian: Reference or beginning point for measuring east or west ranges.
Base line: Reference or beginning point for measuring north or south townships.


How the Township and Range System Works:
A specific township is identified as being north or south of a particular baseline and east or west of a particular principal meridian. For example, T3N, R1E of the 3rd Principle Meridian is the third township north of the baseline in the first range east of the Third Principle Meridian. This particular 36 square-mile area is located in southern Illinois. The land description generally starts with the smallest part of the description and proceeds to the largest definition. For example, SE1/4 of NW1/4 of Section 3, T3N, R1E, 3rd PM would be the southeast quarter of the northwest quarter of section 3 in township 3 north, range 2 east.