Are our freezing temperatures really over for the winter? Chances are: probably not. But there is a chance that your trees may have started to 'wake up' during this winter warm-up.
Trees put on their 'parka' when winter is setting in and unseasonably warm temperatures can cause them to start to shed their 'winter layers'. The drastic change in temperatures that we have had this winter can trick non-native trees into thinking that spring may be here. Native trees know that the swing in temperatures are nothing new, but non-native trees may shed their 'winter parka' and be unable to put it back on again. Native trees and shrubs have long chilling requirements: usually they need 1000 to 1500 hours of temperatures between 32-40 degree Fahrenheit in order to put their 'parka' on and in return have a long thawing process as well. Non-native trees and shrubs aren't quite so lucky.
It the weather does cool off again, you may notice some damage to the tips of non-native trees, which include catalpas, Norway Maple and fruit trees. There may be damage to tree buds and/or some twigs may break and fall. Fruit trees may have damage to their flowering buds.
You may have ice damage from the winter as well. The best thing to do is to wait until spring to assess and fix any damage. If the tree buds feel plumb in the spring, the damage is most likely minimal, but if the twigs are still flexible in the spring then the trees need more time.
Warm air temperatures can also encourage evergreen trees to release moisture back in to the atmosphere, which causes winter desiccation injury, resulting in browning needles come spring. Warm weather also thaws the soil. The thawing in the soil and the releasing of the moisture by evergreens can warrant the need to water these trees in the winter. Water requirements by these trees are minimal and watering should be limited to the younger trees where the snow has completely melted around them.
Your conservation district is a great resource when it comes to determining how much damage has occurred. Reach out to them with any questions!
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