Origin:
This is a native insect in eastern North America.
Biology:
This is one of the largest scale insects in North America with the wax scales growing to ½ inch across. It attacks primarily various species of magnolia trees, and while it rarely causes serious damage the wax and honeydew will cover large areas of the bark. Heavy infestations can cause branch dieback, and if left unchecked trees can be killed. Tiny nymphs overwinter on twigs, becoming active and feeding again in the spring. These develop to tiny winged males and the sessile females that continue to expand. In mid to late summer they produce eggs and then crawlers, and these migrate to suitable feeding sites and remain there through the winter.
Identification:
The very large size and overall dark gray color, along with white wax over the shell, are diagnostic. Their presence on magnolia trees also helps to ID this species.
Characteristicts Important to Control:
Dormant or summer oils may be effective, as well as contact insecticides applied when the first instar crawlers are present. Attention needs to be paid to the small twigs near the ends of branches, as this is where the crawlers will congregate.
