Answer: Scale is notoriously difficult to control. You might try using commercially formulated insecticidal soap according to the label instructions and when the scale are soft and moving or crawling. Be sure to spray the top and bottom sides of the leaves as well as the brnaches and stems and especially where there are joins. Also, a weekly search and destroy mission done by hand under a bright light can make a big dent in the population; gently pop them off with a fingernail. This is the time of year when they seem to peak.
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