雁北地区,海拔1,000-2,300公尺,年平均温度5.1-6℃,降雨量300-617公厘,多集中于7、8月份,占年总降雨量的49-51％。根据莜麦的不同播期,在雁北可分为秋莜麦区、夏莜麦区以及界于二者之间的二不秋莜麦区。秋莜麦区:7月上中旬莜麦进入拔节抽穗阶段,需水最多,而这一地区降雨从6月稳定上升,7月达到最高点,7、8月雨量占全年的51％,因此莜麦的需水关键期和降雨相吻合。7月下旬莜麦进入抽穗开花阶段,气温19.9℃,相对湿度61％,极有利于莜麦的生长发育,所以莜麦在当地种植面积大,栽培历史久。 Yanbei area, 1,000-2,300 meters above sea level, the annual average temperature of 5.1-6 ℃, rainfall of 300-617 mm, mostly concentrated in July and August, accounting for 49-51% of the total annual rainfall. According to the different sowing sowing date, Yanbei can be divided into autumn 莜 wheat area, summer 莜 wheat area and between the two in the autumn 莜 wheat area. Autumn 莜 wheat area: In mid-July, oats entered the stage of jointing and heading, with the highest demand of water. However, the rainfall in this area increased steadily from June to July and reached the highest point in July. The rainfall in July and August accounted for 51% of the whole year. The critical period of water requirement for oats is consistent with rainfall. In late July, the barley entered the stage of heading and flowering. The temperature was 19.9 ℃ and the relative humidity was 61%. It was very conducive to the growth and development of barley. Therefore, barley was planted in the area for a long time and had a long history of cultivation.