Office fields (guantian 官田) were one type of state-owned land (gongtian 公田) in imperial China. Private land was usually called mintian 民田. The term has a narrow and a wider meaning, the latter referring to all abandoned, ownerless or uncultivated land (tu ye wu zhu 土業無主, kenhuang 墾荒), and the narrower pointing at land that was used and cultivated.
State-owned fields served several purposes: Supplying military garrisons, providing the salaries of state officials or the necessities of government institutions like bureaus, schools or shrines, grazing grounds for horses and hunting grounds for the imperial house and princes, wasteland seized by the state and used for various aims, land cultivated with staple crops, and estates of various social groups and government institutions.
Office fields were usually cultivated by tenant farmers, who paid a rent in kind or in money (zu 租), and were therefore not expected to pay the land tax or household taxes (shui 稅). The word zu, even if usually translated as "rent", can therefore be seen as a land tax for government-owned fields.
The ritual Classic Zhouli 周禮 (part Diguan 地官, ch. Zaishi 載師) explains that office fields (guantian), "ox fields" (niutian 牛田), "reward fields" (shangtian 賞田), and pasture land (mutian 牧田) were located in certain distances of the royal capital. The Han-period 漢 (206 BCE-220 CE) scholar Zheng Zhong 鄭眾 (d. 83 CE) explained that office fields was land which "public families" cultivated (gongjia zhi suo geng tian 公家之所耕田). Zheng Xuan 鄭玄 (127-200) remarked that these were commoners who used the land that "the family of a state official had received" (guan zhe qi jia suo shou tian 官者其家所受田). Fields owned by the imperial house of state officials were usually cultivated by serfs, slaves or tenant farmers. In the early imperial age, this type of field was called jitian 籍田 or jietian 藉田.
Another meaning of the term guantian was – in times of turmoil and lower population density – land without owner and not being cultivated. Zhongzhang Tong 仲長統 (179-220), author of the book Changyan 昌言, remarked that the government strictly limited the amount of land a single household could possess, in order to prevent the distinguished families from occupying abandoned land. The state preferred to give this land to individual farmers who were willing to cultivate it. This idea was welded into a law by the Jin dynasty 晉 (265-420) which created the land quota system (zhantian zhi 占田制).
With the introduction of the equal-field system (juntian zhi 均田制), the Northern Wei dynasty 北魏 (386-534) allotted nominally state-owned fields to individual farming families according to certain quotas (koufentian 口分田), and allowed them to cultivate them over generations (yongyetian 永業田). When the family became extinguished, the land returned into government ownership. The Tang dynasty 唐 (618-907) owned imperial estates (huangzhang 皇莊) and parks. At the time, the type of fields to cover administrative expenses (gongxietian 公廨田) was introduced.
From the Song period 宋 (960-1279) on, the term guantian referred to land directly owned by the state or the imperial house. Depending on the particular use, there were different types of office fields, namely salary fields (zhitian 職田, baiguan zhitian 百官職田, guanfentian 官分田), agro-colonies (tuntian 屯田, anbiansuo tian 安邊所田), garrison fields (yingtian 營田), office estates (guanzhuang 官莊), school fields (xuetian 學田) or granary fields (cangtian 倉田). If land owners had fled and left their land alone, the government could seize it (taohutian 逃戶田).
The ownership of state-owned fields was not always clearly on the side of the government. If an emperor bestowed land to a prince, for instance, or a person of merit, the land was in fact private property, even if the right were nominally with the state. The de-facto owners of cultivated land were even granted ("sold", maipu 買撲) the right to collect taxes from the farmers, instead of receiving a rent (Yang 2011, Yang 2012). Mixed types of ownership and collecting rights went even back to early imperial times (Li 2014).
In contrast to earlier times, the Yuan 元 (1279-1368) and Ming 明 (1368-1644) governments regularly usurped private land to use it for various administrative purposes. The Ming dynasty introduced a wide range of new types of government fields returned to the state because the owner had committed a crime (mo guantian 沒官田), private fields fallen back to the state because of missing heirs (duanru guantian 斷入官田), fields once presented to state officials returned to the state (huan guantian 還官田), imperial estates (huangzhuang, huangshi guanzhuang 皇室官莊), pastures (muma caochang 牧馬草場), waste land inside of or close to cities (chengruan muxu di 城壖苜蓿地), land to raise sacrificial animals or such used for state banquets (shengdi 牲地), land of parks, mausoleums and tombs (yuan-ling-fen di 園陵墳地), occupied wasteland (gongzhan xidi 公占隙地), estates presented to dignitaries and persons of merit (ciqi zhuangtian 賜乞莊田), and agro-colonies cultivated by troops (juntun 軍屯, weisuo tuntian 衛所屯田), by commoners (mintun 民屯) or owned by salt merchants (shangtun 商屯). There was also state-owned land in remote regions which served to yield anti-corruption allowance (bianchen yanglian tian 邊臣養廉田).
In the region of Jiangnan 江南, the Ming dynasty created new types of government-owned fields (jin'e guantian 近額官田, jin'e guantian 今額官田) for which the rent was substantially higher than of the traditional state-owned fields. The statecraft encyclopaedia Da-Ming huidian 大明會典 provides figures for 1502 which show what all private land of the Ming empire summed up to 4.2 million qing 頃 (see weights and measures), while state-owned land had a total size of just 0.598 million, which is about 14 per cent (Yang 1998).
The Qing dynasty 清 (1644-1911) added to these the types of Banner land (qitian 旗田, baqi zhuangtian 八旗莊田), estates of the Imperial Household (neiwufu zhuangtian 內務府莊田) and sacrificial fields (jitian 祭田). In the late decades of the Qing period, state officials – members of the gentry – and other land owners used to occupy state-owned land. At the end of the imperial age, cultivated fields were all in private hands.