Answer: Based on your description I suspect the plant is being attacked by scale insects. You might inspect the plant carefully for these little disk-like sucking pests which tend to be active in late winter. When in the soft almost waxy "crawling" stage they can be treated with insecticidal soap (follow the label instructions) or gently scraped off with a fingernail. They are well camouflaged and may be difficult to see, but you will find them on the stems and bark as well.
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