果树即使在适生区栽培，冬季也有可能发生冻害，特别管理差、树势弱的园片，在严寒年份的冬季，容易发生冻害。作为枝干来说形成层最抗冻，其次为树皮、边材和髓。一般冻害的程度与降温速度、低温长短和解冻快慢有关，即降温越快、温度越低、时间越长、解冻越猛，受害越重。枝 Even if fruit trees are cultivated in suitable habitats, frost damage may occur in winter, especially for poorly managed or diseased shrubs. In cold winter, the frost damage is easy to occur. The formation of the most resistant to freezing as a branch, followed by bark, sapwood and pulp. The degree of general frost damage and cooling rate, the length of the low temperature and thawing speed, that is, the faster the temperature, the lower the temperature, the longer the time, the more thawed, the more victims. branch