Damage to Arborvitae Branches

Western arborvitae (Thuja plicata), also referred to as red cedar, which is a coniferous evergreen tree that grows in U.S. Department of Agriculture plant hardiness zones 5 through 8. The tree grows 50 feet tall or more in well-draining soil and full to partial sun. Overall the arborvitae is a low-maintenance tree, but occasionally damage to branches does occur.

Deer

Deer have a huge preference for arborvitae. They enjoy the eastern variant but will nibble on the western variant too. At the spring, they will strip the new foliage from the lower portion of their tree. In the winter they’re content to consume the old leaf when food is less plentiful. Besides leaving bare branches, they also break the wood when they pull to the strategies or scratch their antlers on the tree. A tall fence can keep deer in the tree, however, sprays that produce the tree odor or taste awful will also assist. If the branches don’t start to recover by the next spring, remove them.

Bagworms

Bagworms infest trees in the spring and summer months. Bagworm moth eggs hatch in the spring and the larvae feed on the tree while they construct the hanging cocoon that will protect them as they grow into moths. The cocoons look like cones with fringe-like extensions. Bagworms hurt the branches, causing them to lose leaf that may not return. Remove the bags in the branches before spray and spring using a bt insecticide to control the worms.

Winter and Salt

Winter frost damage and salt damage are similar in appearance. Winter frosts are more likely to affect younger trees. The damage from frost or salt seems as brown or red needles on the outer borders of the tree in which the contact occurred. Winter damage is usually worse on the face of the tree that gets hit by wind. The broken sections of the branches should be trimmed back to healthy growth. If the damage affects all the needles on the branch, remove the whole branch. Add a wind or salt screen to protect the tree in repeat damage if at all possible.

Passion

Passion is frequently fatal to western arborvitae, and the broken tree is lost. According to the University of Nevada’s JoAnne Skelly, so long as there is some green to the tree and it is not a hazard to people or buildings, it can be left until the next spring so that the damage could be better assessed. When there is some blackening at the tip of the branch, but it still contains live foliage, just trimming the tips back to a grass. If the branch has no leaf or buds, it will most likely need removed. Waiting until the next spring will permit the buds time to develop and either die off, or form new leaf.

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