The also grow in arable lands, both cultivated and fallowed, and in pastures. Fields in established and stable shifting cultivation systems are cultivated and fallowed cyclically. When rice land is fallowed, populations seem to then move away from adjacent ditches. Nests have been found near open regions of fallowed land and man-made ditches. These soils are left fallowed during dry season due to lack of irrigation and rainfall. According to a 1990 pilot study, water diversions and fallowed farm land reduced farming employment. One of the two or three fields was fallowed each year to recover soil fertility. Opening of new mines and processing facilities fallowed. Fallowed land, pastures, forests, and wasteland were held in common.