Why Use Wrap
Tree wrap is used to protect young, thin-barked trees during the winter months. Wrapping trees helps protect against sunscald and frost cracks, both of which are temperature related. Not all trees need to be wrapped. Species such as linden, maple, ginkgo, crabapple, and redbud will benefit from tree wrap. Trees with thick, corky bark, like bur oak, do not need to be wrapped.
Sunscald
Sunscald is also known as “southwest injury” since it tends to occur on the south or southwest side of the tree. During the winter, the south/southwest side of the tree is warmest, due to the location and angle of the sun during the winter months. Sunny warm winter days cause cells in the living tissues of the tree’s trunk to lose dormancy. As temperatures drop at night, the cells freeze, burst, and die. Sunscald creates a jagged wound along the trunk that can take a long time to seal over and creates an entry point for disease and insects. [Figure 1]
Frost Cracks
Frost cracks are vertical cracks in the trunk or stems of trees. Warm winter days cause the cells to warm up and expand. As the sun sets, the outer bark temperature cools quickly, but the inside of the tree remains warmer, which results in splitting. Younger trees are most susceptible. Frost cracks are usually not as detrimental to tree health as sunscald.
Steps for Wrapping Trees
- Wrap trees at the end of November and remove wrap in early spring (mid-April). Tree wrap should not be left on all year.
- Use a light-colored crepe-paper type wrap; using plastic, dark colored materials or burlap can result in tree damage. Crepe-paper wrap has some elasticity to it and sheds water, keeping the trunk dry. [Figure 2]
- Start wrapping at the bottom of the tree, overlapping by 1/3 until you reach the first branch. Tape the wrap to prevent it from slipping at the top of the tree. Or consider stapling the wrap to itself around the first branch. Do not staple the wrap into the tree!
- Once the bark of the tree has hardened and become furrowed, it is not necessary to wrap trees. Trees should only be wrapped for the first one to three years following planting. It cannot be emphasized enough that wrapping is only a seasonal treatment.
Watch this short video on tree wrapping.
Using Latex Paint
- This is not the preferred method and is uncommonly used in home landscapes
- Latex paint is often used in nurseries and orchards. It is a cheaper and less labor-intensive option to wrap trees individually.
- Paint is not as aesthetically pleasing and will take time to wear off.
- Only use water-based latex paint and not oil-based, as it can damage trees.
- Apply the paint in late fall when temperatures are above 50 degrees F so it can dry quickly.
This publication, reference GardenNotes #653, is developed as part of the Colorado State University Extension Master Gardener Program.