Tree wrap, typically made of paper, burlap, or plastic, serves as a temporary protective layer for the thin bark of young or newly planted trees. This material is applied directly to the trunk, creating a barrier against various environmental and biological threats. Understanding its purpose and the precise time for its removal is essential for ensuring a tree’s healthy development.
Purpose of Tree Trunk Wrapping
Tree wrap protects the bark from sunscald, or southwest injury, which occurs during the winter months. On sunny winter days, dark bark absorbs solar radiation, warming the tissue and breaking dormancy, especially on the south or southwest side of the trunk. When temperatures rapidly drop at night, this newly active tissue freezes and dies, leading to vertical cracks and wounds. The wrap, particularly light-colored varieties, reflects sunlight to stabilize the bark’s temperature, preventing this damaging freeze-thaw cycle.
Beyond temperature regulation, the wrap provides a physical defense against mechanical and biological damage. It shields the smooth, young bark from accidental injuries caused by maintenance equipment like weed trimmers or lawnmowers. The barrier deters foraging animals such as rabbits, voles, and deer from gnawing or rubbing on the trunk, which compromises the tree’s vascular system. This protection is generally needed for the first two to three years following planting until the tree develops its natural, more rugged bark.
Crucial Timing for Wrap Removal
The protective wrap must be removed at the end of the dormant season, which generally falls in late winter or early spring. A common recommendation is to apply the wrap in late fall, around November, and remove it by mid-April or the time of the last hard frost. The goal is to keep the trunk covered only during the period when sunscald and animal damage are most likely to occur. Leaving the wrap on even slightly into the warmer months can quickly lead to severe complications that negate the winter protection provided.
Hazards of Leaving Trunk Wrap On
Failing to remove the trunk wrap promptly in spring creates problems that can quickly kill a young tree. One serious hazard is girdling, which occurs when the non-flexible wrap constricts the trunk as the tree increases in diameter during the growing season. The tightening material digs into the bark, cutting off the flow of nutrients and sugars through the phloem layer, effectively starving the tree. This disruption of the vascular system leads to a rapid decline in health and often results in death.
The wrap also creates an environment conducive to pests and disease. The material traps moisture against the bark, creating a damp, warm microclimate that encourages the growth of mold, fungus, and rot. The sheltered space between the wrap and the trunk becomes an attractive hiding place for insects, borers, and rodents during the warmer months. These pests can damage the bark and wood, disrupting nutrient flow and introducing pathogens.
Safe Removal and Post-Care Steps
The removal process should be done with care to avoid accidentally scoring or damaging the young bark. Use a sharp tool, such as scissors or a utility knife, to carefully cut the wrap vertically along the trunk. The cut must be made away from the bark, ensuring the blade never makes contact with the living tissue underneath. Once the material is cut, it can be gently unwound from the trunk.
It is necessary to remove all components of the wrap, including any tape, twine, or ties used to secure it. These small pieces are often the primary cause of girdling injuries as they do not degrade and become embedded in the expanding bark. After the wrap is fully removed, the trunk should be inspected for any signs of damage, such as wounds, discoloration, or evidence of pests. Ensure the base of the trunk remains clear of debris and that the root flare—where the trunk widens at the soil line—is fully exposed to the air.