Plants develop whitish growth on stems and leaves, on the tops and bottom. Leaves become mottled, turning yellow.
Infested plants are difficult to control. Plants can be sprayed in early spring (March) with an horticultural oil. Homeowners should be warned that the oil spray will cause the plant to defoliate. Stems and leaves can also be removed and composted. New growth may be fortunate and not become infested.
Insecticide sprays can be applied when the scale crawlers are actively moving and haven't created their shells. This period usually occurs during June when fringetrees, (Chionanthus), cockspur hawthorn (Crataequs crusgalli), Beautybush (Kolkwitzia) and Late Lilac (Syringa villosa) are in bloom.
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