我省从人工栽培大叶桑品种以后,一直沿用南方的夏伐法剪伐.由于我省冬天气候寒冷,早春温差较大,无霜期较短,桑树夏伐以后生长期缩短,技条生长细弱,木质不充实,年年遭受不同程度的冻害.遇到特殊年份,枝条冻害率达70% Since the cultivation of Eucalyptus mulberry cultivars in our province, it has been used for cutting in the south by means of the summer cutting method.As a result of the cold winter in our province, the temperature difference in early spring is relatively large, the frost-free period is short, the growth period of mulberry trees is shortened after summer cutting, Wood is not full, suffered varying degrees of frost damage every year.Experienced a special year, branches frostbite rate of 70%