|Activity 4: Tier and Range|
|In most of the United States, tier
and range is a common method used for locating position and is part of the
U.S. Public Land
Survey introduced in
the 1785. It is
used in all states except the original 13 and Maine, Vermont, West Virginia, Kentucky,
and Tennessee. Texas
is also not part of this system because it was originally surveyed using the Spanish land grant
system. The tier
and range system was
designed primarily for locating property lines and land description on legal documents. It is more commonly used to
locate parcels of land, although it can be used to locate a point. Numerous principal
meridians and baselines have been established for the middle and western
parts of the
United States and are
used for determining location over different sized areas (Fig. 1).|
Selected north-south lines, principal meridians, and east-west lines, baselines (Fig. 1), define the tier and range system. Although the tier and range system was supposed to be completely rectangular, some townships and sections are irregular in shape because of problems with the original surveys.
Range lines are parallel to the principal meridian on 6-mile intervals. The strips of land between these lines are ranges and are numbered consecutively north and south of the principal meridian. At right angles to the range lines and also at 6-mile intervals from the baseline are tier lines. These lines define strips of land, tiers, parallel to the baseline. The intersection of a tier and a range creates a square of land, a township, 6 miles on a side. Specifying the tier (T3N) and range (R2E) that intersect identifies a township. A township covers an area of 36 mi2.
Townships are subdivided into a series of 1-mi2 sections, each covering 640 acres. They are numbered starting at one in the upper right corner of the township (Fig. 2). To provide a more precise location, sections are quartered and each quarter section identified by the quadrant it occupies. Quartering a section identifies a location within a square (a quarter section) a half a mile on each side. If greater spatial accuracy is required, quarters can be further quartered to produce eighth sections—i.e., squares a quarter mile on a side. Listing the subdivisions starting with the smallest, sixteenth, eighth, quarter, and working out to the range and tier specifies a point’s location. For example, the location of the parcel of land denoted by the shaded portion of section 27 in Fig. 2 is NE1/4, SW1/4, Sec 27, T3N, R3E. A point can be located by specifying the quadrant the point is centered in.
Fig. 2: Numbering of sections in a township.