Answer: Japanese Blueberry Tree (Elaeocarpus decipiens) is an evergreen, but as with all broadleaf evergreens, the oldest foliage is shed after 2-3 years to make way for healthy new foliage. The oldest leaves turn red (as the tree extracts all of the carbohydrates), and then they fall off. Healthy trees will replace these lost leaves in a few weeks. As long as your tree is putting on new growth while it's dropping the oldest leaves, the process is natural and shouldn't cause concern. It will fully leaf out before summer arrives.
Best wishes with your landscape!
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