Blog · September 30, 2026
What Is an Aliquot Part?
An aliquot part is a standard fraction of a section, such as a quarter or a quarter of a quarter, created by the rectangular survey. The words name a piece of the section. They are not a lot number in a subdivision plat.
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Halves and quarters of the section
Aliquot descriptions divide a section by halves and quarters using the section lines and quarter lines. The northeast quarter is an aliquot part. The southeast quarter of the northwest quarter is a smaller one, often near forty acres in a regular section, and often called a forty. The language runs from the smallest piece back out to the section, then to township, range, and meridian. Order matters. The northeast quarter of the southwest quarter is not the southwest quarter of the northeast quarter. They lie in different parts of the section. Sketch the section, quarter it, and shade the last fraction named as you read from the large piece to the small one, or the reverse, as long as you stay consistent with the grammar of the sentence.
What aliquot does not include
Government lots along the north and west of a township, and along meandered water, are numbered lots. They are not aliquot parts, because they were not regular halves or quarters. A metes-and-bounds exception inside a forty is not an aliquot part either. A subdivision lot called Lot 4 is not an aliquot part even if someone says it is about a quarter of the block. When a deed mixes an aliquot caption with a metes-and-bounds exception, read both. The aliquot phrase gives the parent piece. The exception cuts something out. The county parcel number may encode section, township, and range, and it may split aliquots into tax parcels that do not match the fractions. The code is an account. The words in the deed are the description.
Area is a result, not the name
People say forty acres as a nickname for a quarter-quarter. In a regular section that is the nominal area. Excess and deficiency, roads, and exceptions change the ground. A call that says the southeast quarter of the southeast quarter, containing forty acres more or less, is still an aliquot call. The fraction is the controlling description if monuments and lines support it, and the acreage phrase is often the weaker part of the sentence. Do not redraw the forty to force a GIS acreage number to equal forty. The assessment map’s acreage is a computed figure for tax rolls. It is not a new survey of the aliquot lines.
What to do next
- Parse the fractions from the larger piece down to the smaller.
- Draw a section square and shade only the last piece named.
- Separate numbered government lots from aliquot fractions.
- Keep township, range, and the meridian with the section number.
The mix-up to avoid
Reading the fractions in the wrong order and shading the diagonal forty. One swapped quarter puts the description on the other side of the section.
Questions people ask
Is the north half an aliquot part?
Yes. Halves and quarters of a section, and halves and quarters of those quarters, are the usual aliquot parts. A strip described only by a width in feet, such as the east 200 feet, is a metes description of part of the section, not an aliquot name.
Can two aliquot deeds overlap?
They should not, if both are regular fractions of the same section. Overlap usually means a misread fraction, an exception that was ignored, or a deed that also calls metes and bounds in conflict with the aliquot words. The cure is to read both full captions, not to average two parcel polygons.
Find the county map
The county GIS map is the practical place to start. Find it from the Platbookmapper directory, then treat the recorded plat and deed as the documents behind the picture.
Not a survey. County GIS and tax parcel maps are assessment and planning layers. They are not a substitute for a recorded plat, deed, or licensed survey.