Q&A - How to get rid of Japanese maple scales
I have lots of these bugs on my Japanese Maple tree. What are they and can I get rid of them?
These are Japanese maple scales. There are several options for removing them. You can use dormant oil during the winter or early spring or horticultural oil later in the year. There are also some systemic soil drenches that are available. Another option that does not require any chemicals but a little work is to scrub them off with a soft brush and soapy water, followed by a rinse with a stream of water. Chris and Mike Dennison go on to talk about the scales themselves.
Mike Dennison was referencing Commercial Insect and Mite Control for Trees, Shrubs and Flowers page 33 out of the UT Redbook
Japanese Maple Scale
Japanese Maple Scale: An Important New Insect Pest in the Nursery and Landscape