public land survey system(redirected from BACK 40)
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public land survey system (PLSS)
A way of subdividing and describing land in most of the United States.Texas, Hawaii, and most of the original 13 states are not described by the PLSS.The system starts with a principal meridian, which is a north-south line.There are 37 principal meridians in the United States. Each principal meridian has a base line that runs east and west through it. Land is described as being east or west of the principal meridian, and north or south of the range line associated with that meridian. Land is typically divided into 6-milesquare townships.Townships are described with reference to their principal meridian and base line.
Example: A township “2 North, Range 3 East, Mount Diablo Meridian” would mean the township is in the second tier north of the base line, and the third column east of the Mount Diablo Principal Meridian.
Each township is then divided into 36 sections.Each section is 1 mile square and contains approximately 640 acres, makingallowance for unsophisticated measuring tools employed at the time of creation.
Sections may be further subdivided into quarter-sections (160 acres),quarter-quarter sections (40 acres),or any other mathematical subdivision.The gray square in the figure on the bottom right might be described as “the northeast quarter of the northwest quarter of the southeast quarter of Section 14, Township 2 North,Range 3 East of the 6th Meridian.