Aerial photo taken on June 2, 2020 shows agricultural technicians conducting yield monitoring at a wheat field in Xidiqiu Village of Linzhang County, Handan, north China's Hebei Province. Agricultural technicians conducted a yield monitoring in Linzhang on Tuesday, a step for the large-scale harvesting of wheat. The mechanical reaping works of wheat in Hebei will last from June 5 to 21. (Xinhua/Wang Xiao)

Agricultural technicians conduct yield monitoring at a wheat field in Xidiqiu Village of Linzhang County, Handan, north China's Hebei Province, June 2, 2020. Agricultural technicians conducted a yield monitoring in Linzhang on Tuesday, a step for the large-scale harvesting of wheat. The mechanical reaping works of wheat in Hebei will last from June 5 to 21. (Xinhua/Wang Xiao)

An agricultural technician checks the grains of wheat at a wheat field in Xidiqiu Village of Linzhang County, Handan, north China's Hebei Province, June 2, 2020. Agricultural technicians conducted a yield monitoring in Linzhang on Tuesday, a step for the large-scale harvesting of wheat. The mechanical reaping works of wheat in Hebei will last from June 5 to 21. (Xinhua/Wang Xiao)

Agricultural technicians conduct yield monitoring at a wheat field in Xidiqiu Village of Linzhang County, Handan, north China's Hebei Province, June 2, 2020. Agricultural technicians conducted a yield monitoring in Linzhang on Tuesday, a step for the large-scale harvesting of wheat. The mechanical reaping works of wheat in Hebei will last from June 5 to 21. (Xinhua/Wang Xiao)

An agricultural technician conducts yield monitoring at a wheat field in Xidiqiu Village of Linzhang County, Handan, north China's Hebei Province, June 2, 2020. Agricultural technicians conducted a yield monitoring in Linzhang on Tuesday, preparing for the large-scale harvesting of wheat. The mechanical reaping works of wheat in Hebei will last from June 5 to 21. (Xinhua/Wang Xiao)

Agricultural technicians conduct yield monitoring at a wheat field in Xidiqiu Village of Linzhang County, Handan, north China's Hebei Province, June 2, 2020. Agricultural technicians conducted a yield monitoring in Linzhang on Tuesday, a step for the large-scale harvesting of wheat. The mechanical reaping works of wheat in Hebei will last from June 5 to 21. (Xinhua/Wang Xiao)