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Article #58, April, 2002
By Bill Cook

     Acres and forties are familiar terms describing land area.  How familiar are related terms such as prime meridian, initial point, and standard parallels?  Do we really understand how “acres” and “forties” were created?  How do township and range lines fit into the picture?

      The following is an example of a legal description for a forty:  T39N, R23W, Sec.4, NW1/4 SW1/4.  The township “T” and range “R” describe the location of a particular township (36 square miles).  The southeast corner of this township lies about 234 miles north and 138 miles west from the initial point, located about 12 miles north of Jackson.  The forty is located in section four (640 acres), and is the northwest quarter (40 acres) of the southwest quarter (160 acres).  Punctuation is important in legal descriptions.  Simply placing a comma between the two “quarters” will describe 320 acres, rather than 40 acres.

      Public land survey was critical to the settlement of the new territories during the decades of U.S. expansion and is just as important today when we deal with land.

      Europeans imported their concept of land ownership to North America.  Try to imagine the problem of opening up new territories to settlement without an efficient way to describe ownership.  Try to design a system that could work across the growing country, especially with the technology of the mid-1700s!

     The first efforts were those used by early settlers.  This “metes and bounds” system can be best described by the following example.

      ". . . after turning around in another direction, and by a sloping straight line to a certain heap of stone which is by pacing, just 18 rods and about one half a rod more from the stump of the big hemlock tree where Philo Blake killed the bear; . . ."

      This was not going to work as settlers began surging west.  So, Thomas Jefferson led the way to resolve this challenge in 1784 and Congress eventually settled on a system in 1796 called the “rectangular survey”.    

      In Michigan, this survey began with an “initial point”, determined by astronomical observations.  From there, a “prime meridian” ran north and south, and a baseline ran east and west.  Along the prime meridian, points were marked at 24-mile intervals.  From each of these points, “standard parallels” were run east and west, also with marked intervals every 24 miles.

      As this grid expanded across Michigan, it was filled-in with 16 townships per 24-mile by 24-mile block.  Each township was six miles on a side containing 36 “sections” of one square mile.  Each section was eventually subdivided into 16 “forties”.

      Today, plat books for each Michigan county reflect changes in our public land survey system since its creation in the 1800s.  Plat books can be used to identify the owner of a particular tract of land.  An index lists all the owners within the county and where their properties are located.  In the front, an excellent description of our current survey can be reviewed.  Parcels are becoming smaller and more numerous, which results in challenges for natural resource management and protection. 

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Bill Cook is an MSU Extension forester providing educational programming for the entire Upper Peninsula. His office is located at the MSU Upper Peninsula Tree Improvement Center near Escanaba. The Center is the headquarters for three MSU Forestry properties in the U.P., with a combined area of about 8,000 acres. He can be reached at cookwi@msu.edu or 906-786-1575.

Prepared by Bill Cook, Forester/Biologist, Michigan State University Extension, 6005 J Road, Escanaba, MI  49829
906-786-1575 (voice),  906-786-9370 (fax),  e-mail:  cookwi@msu.edu

Use / reprinting of these articles is encouraged. Please notify Bill Cook.
By-line should read "Bill Cook, MSU Extension" Please use the article trailer whenever possible.

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