mu [Chinese. 畝]

In China, an ancient unit of land area; since 1959, two units, both metrified forms of an earlier unit. See history. Also romanized as mou.

In the market system (shì zhì ) as applied to agricultural land, = 666 ²⁄₃ square meters (UN, 1966).

In the gon zhì system , a metrified version of the shì zhì system, another unit, the gongmu, also applied only to agricultural land, = 100 square meters.

The mu does not appear in the standard metric system (gong zhì) or in the shì zhì system as applied in general, whose units of area are all squares with sides equal to the shì zhì units of length.

2

In Taiwan, a unit of land area = 30 p'ing, about 99.174 square meters (about 0.02451 acre). This value is about 0.14876 shì zhì mu.

History

In the early Zhou the mu = 100 square bu. (The 100-bu mu was sometimes called a xiaomu or Zhou mu.) Around 350 bce, a mu of 240 bu was introduced (sometimes called a damu). Conceptually, it was a strip of land one bu wide and 240 bu long, or a plot 15 × 16 bu. After a period of coexistence, in 104 bce the 240-bu mu became the general standard, and thereafter varied as the number of chi in a bu and the length of the chi changed.

There was a great deal of regional and local variation.

Period	Size of mu, square meters
Early Zhou	192
Han to Tang	457-523
Song	573
Yuan	840
Ming	640
Qing	706
Shanghai, by order of the Municipal Council	6,600 square feet
customs treaty	920.417 square yards 769.59 square meters based on a chi of 14.1 inches

Ochi Shigeaki.
Ichiho hihyakuyonjû-ho sei o megutte. (On the 240-bu mu system).
Tōhōgakuhō, vol. 53, pages 21–35 (1977).