河北省和京、津一带,地处我国冬小麦种植的北部边缘,由于冬冷春寒,气候多变,每年都有不同程度的冻害发生。建国三十五年来,有十二个冻害年,大体是三年一遇。一般年份越冬死苗常占10-15%。近八年出现过四次重冻害年和一次轻冻年。1957、 Hebei and Beijing, Tianjin area, is located in the northern edge of winter wheat cultivation in our country, due to the winter cold spring, climate change, varying degrees of frost damage every year. Thirty-five years since the founding of the People’s Republic, there are twelve frostbite years, which are generally once every three years. Common winter winters often account for 10-15%. In the past eight years there have been four freeze-year and one freeze-year. 1957,