Origin:
Native to North America.
Biology:
Immature stages overwinter on the bark of the tree, resuming activity and feeding in the spring and maturing to adult females in the summer. The female produces large numbers of eggs under her wax cover, and these hatch to the mobile crawler stage in late summer. Tulip and magnolia trees are most commonly infested, but these scales also may be found on hickory, redbud, walnut, and others. There is a single generation each year. The expired scale of the female may persist on the tree for one or two years after she is dead, leading to concern that an infestation is continuing. Heavy infestations can kill smaller trees, and cause branch dieback on larger trees.
Identification:
This is a relatively large scale, and as the adult female presents a very convex, rounded shape with a rather pitted and lumpy surface. Coloring is a range from grayish to brown with a pink tint, with patches of darker color over the surface.
Characteristicts Important to Control:
Where populations of the scale warrant control dormant or summer oils may be effective, as well as contact insecticides applied when the first instar crawlers are present. An IGR applied when crawlers are present also may be effective.