The "square foot (US survey)" is a unit of area used in the United States primarily for land surveying and mapping purposes. It differs from the standard square foot because it is based on the U.S. survey foot, which is a historical unit of length used in land surveying in the United States. The U.S. survey foot is slightly different from the international foot.
One square foot (US survey) is equal to approximately 0.0929034119223 square meters (m²) or about 0.111111 square yards (yd²).
This unit is used in various land-related applications, particularly in the United States, where the U.S. survey foot and the square foot (US survey) are still employed for legal and historical reasons in certain land surveys and property descriptions. It's essential to be aware of the specific units being used when dealing with land measurements to avoid any discrepancies or errors.
A square perch, often referred to as a "square pole" or simply "perch," is an obsolete unit of land area measurement. It was historically used in some English-speaking countries, including the United States and the United Kingdom, for land surveying and property descriptions.
One square perch is equivalent to one square rod or one square pole. In terms of modern measurements, one square perch is approximately equal to 25.29285264 square meters (m²) or 0.00625 acres.
Like other obsolete units of land area measurement, the square perch has largely been replaced by more standardized systems of measurement, such as square meters and square feet, in modern times. It is rarely encountered in contemporary land transactions or legal documents.