Winter Watering is Important to Evergreen Trees
All trees, and in particular the evergreen trees, transpire or lose water during the winter months. The lack of water can have detrimental effects on the tree in a number of ways.
Two such effects include winter burn and winter drying. Winter burn is the browning of evergreen needles caused by rapid temperature changes. Winter drying is the dessication of foliage and twigs by warm, dry winds when water conduction is restricted by the freezing of plant tissues or by frozen soil.
According to Sarah Browning, UNL Extension Educator, all trees transpire, or lose water, even during the winter months. Sometimes this loss is greater than the roots can replace and drying damage results. Minor damage results in reddening or browning of foliage, which may later recover. Symptoms of more severe injury include browning and subsequent death of branch tips or entire branches. The side of the tree facing prevailing winds is most susceptible to winter drying.
Often, a combination of winter burn and winter drying will occur, occasionally complicated by drought. If damage is severe enough, affected branches may die. Sometimes, the entire tree may be killed.
It is good to water trees thoroughly in the fall, deeply soaking the root systems, ideally before winter mulch is applied. Then, continue watering monthly in winter when the soil is not frozen or during dry periods with little precipitation. In particular, new plantings installed during the past spring and summer should be emphasized in the watering process.
