核桃幼树安全越冬技术措施我国北方地区年降雨量较小，特别是１－２月份气候寒冷干燥，蒸发强度大，而核桃枝条髓部中空，组织疏松，保水力较差，枝条易蒸腾失水，此时土壤冻结，根系活动微弱，处于休眠状态，不能从冻土层中吸收水分补充地面蒸腾所需，在这种地上地下供需... Winter walnut trees overwintering technical measures China’s northern rainfall is small, especially January to February cold and dry climate, evaporation intensity, and walnut branches hollow, loose tissue, poor water retention, transpiration-prone branches , At this time the soil is frozen, the activity of the root system is weak, and is in a dormant state, and can not absorb the moisture from the permafrost layer to supplement the ground transpiration required for supply and demand on the above and below ground.