Cottony Camellia Scale

Cottony camellia scale is a sap-feeding insect that infests camellia, holly, yew, euonymus, and maple. Infested plants usually have a significant amount of black sooty mold growing on the sugary “honeydew” or liquid waste produced by these insects.  Heavy infestations may cause leaves to turn light green in spring (Figure 1).

The easily overlooked flat females live on undersides of leaves and are about 1/8 inch long, oval, and yellowish-tan with a brown margin. However, they produce very noticeable elongate white cottony sacs containing several hundred eggs (Figures 2).

Figure 1. Cottony camellia scale causes sparse foliage and yellowed leaves on this holly, and white egg sacs of cottony scale are present. (Photo: A. Heisdorffer)

Figure 1. Cottony camellia scale causes sparse foliage and yellowed leaves on this holly, and white egg sacs of cottony scale are present. (Photo: A. Heisdorffer)

Figure 2. White egg sacs of cottony Camellia scale (400 to 600 eggs per sac) (Photo A. Heisdorffer)

Figure 2. White egg sacs of cottony Camellia scale (400 to 600 eggs per sac) on holly leaves. (Photo A. Heisdorffer)

 

Management Alternatives

  • Light infestations often can be managed by hand-picking and destroying infested leaves. Remove any cottony egg masses found on leaves in mid- to late May.
  • Prune and destroy more heavily infested leaves and branches when practical.
  • Crawlers hatch from eggs from late May through June. They settle on the undersides of the leaves to feed on sap and grow through winter. This stage is most vulnerable to control with insecticides or insecticidal soap. Use of insecticidal soap helps to preserve natural enemies of the scale.
  • Use a superior dormant oil spray during winter to kill overwintering scales on foliage.

 

By Lee Townsend, Extension Entolomogist

 

 

Posted in Landscape Trees & Shrubs