Common land units
a. Acre
- Is a unit of area equal to 43,560 square feet, or 10 square chains, or 160 square poles. A square mile is 640 acres. The Scottish acre is 1.27 English acres.
b. Arpent
- Unit of length and area used in France, Louisiana and Canada. As a unit of length, an arpent is approximately 191.8 feet. The (square) arpent is a unit of area, approximately .85 acres.
c. Gunter’s chain
- Unit of length equal to 66 feet, or four poles. This unit was apparently defined as one tenth of a furlong, a common unit of length in the old days.
- The mile was redefined from 5,000 feet to 5,280 feet in order to be an even multiple of furlongs. A mile is 80 chains.
d. Chain
- Unit of length usually understood to be Gunter’s chain, but possibly variant by locale. Chains equal to two poles (one half the standard lengths) are found in Virginia.
- The name comes from the heavy metal chain of 100 links that was used by surveyors to measure property bounds.
e. Engineer’s Chain
- A 100-foot chain containing 100 links of one foot apiece.
f. Hectare
- Metric unit of area equal to 10,000 square meters, or 2.471 acres.
g. Hide
- Old English unit of area usually equal to 120 acres.
h. Labor
- The labor is a unit of area used in Mexico and Texas. In Texas it equals 177.14 acres (or one million square varas).
i. League (legua)
- Unit of area used in the southwest U.S., equal to 25 labors, or 4,428 acres (Texas), or 4,439 acres (California).
j. Link
- Unit of length equal to 1/100 chain (7.92 inches).
k. Poles
- Unit of length and area.
- Also known as a perch or rod.
- As a unit of length, equal to 16.5 feet. As a unit of area, equal to a square with sides one pole long. An acre is 160 square poles. It was common to see an area referred to as “87 acres, 112 poles” – meaning 87 and 112/160 acres.
l. Rood
- Unit of area usually equal to 1/4 acre.
m. Vara
- Unit of length (the “Spanish yard”) used in the southwest.
- The vara is used throughout the Spanish-speaking world and has values around 33 inches, depending on locale. The legal value in Texas was set to 33 1/3 inches early this century.