acquisitions from Native American Indians and foreign powers. It encom-
passes major portions of the land area of 30 southern and western states.
Almost 1.5 million acres were surveyed into the PLS system of townships,
ranges, and sections.
The PLS is a hierarchical land subdivision system that makes it possible
to locate land. The hierarchy begins with two of the 34 meridians, which are
distinct and unrelated to other PLS meridians. The 34 principal meridians
run north-south. Each is named, and allows the identification of different
surveys. The meridians meet baselines, as they are called, which run east-
west and are perpendicular to a principal meridian. The first subdivision of
6 mile units is organized by townships , which indicate the
location north or south of a baseline, and ranges , which indicate the location
east or west of a principal meridian. Each 6
6 mile unit is called a township
and is further theoretically divided into 36 equal 1
1 mile sections. Each
section has a theoretical area of 640 acres and can be further divided into
aliquot parts including half sections, quarter sections, and quarter-quarter
sections. (See Figure 5.4.) The location of all land in this system consists of
Nested hierarchical organi-
zation of the U.S. PLS.