This insect pest has been terrible on some plants in the past few seasons. Plants that are stressed, from drought or other factors, are more susceptible to damage. Euyonmous is one plant particularly hard hit by this pest. The most visible stage of this insect is a shell-like form which sticks to stems and leaves. Some forms, like Euyonmous scale or Cottony scale have white cottony stuff covering them. Magnolias get a large scale like an oyster shell. Scales weaken the plants they are on and can eventually kill it.
Because of the protective shell, a systemic insecticide, like Orthene, may be needed. Best approach may be to use a horticultural oil early and late in the season and another pesticide in May-June, depending on the scale. The oil smothers the scale stage while the other pesticide kills the crawling stage. Avoid using plants that are susceptible to scale, such as Euyonmous "Silver King".