“Winter burn” refers to the browning or bleaching of evergreen foliage during the winter. This can happen for four reasons:
- Sun and wind cause trees to lose water throughout the winter. Their frozen roots are unable to replace this lost water. This results in the browning of the plant tissue.
- Sunny days warm the tree’s tissue, which in turn initiates the cellular activity. When the sun sets, the tree’s temperature drops to harmful levels and the activated tissue dies.
- During sunny winter days, chlorophyll in the foliage is destroyed (photo-oxidized). The tree does not re-synthesize when temperatures are below 28 degrees Fahrenheit. This is what causes bleaching.
- Cold temperatures in the fall or late spring can result in injury or death of tree tissue.
Treatment: You can prevent injury by creating a barrier of burlap or similar material on the south, southwest, and windward sides of evergreens. If all sides of the tree are showing signs of injury you can surround the whole tree, but you should leave the top open to allow air and light in.
Contact a Certified Arborist like us Johnson ops Tree Care to assess your trees.