Answer: Evergreen trees and shrubs retain their leaves for about three years. After that period of time the old leaves fall off and new leaves appear the following spring. The older leaves are on the insides of the branches closest to the trunk. As long as the foliage near the tips of the branches remains green and healthy looking, your cedar trees are just fine and there's no need to be concerned about the old foliage dropping. Sometimes evergreens develop insect problems. Spider mites can do damage to the foliage towards the center of the tree because of their feeding. You might check for fine webbing on the stems and branches and foliage. These pests like dry, dusty accommodations and you can discourage them by periodically hosing off the tree, directing the water spray towards the inside leaves and branches. Once a month or so should discourage these pests.
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