Includes Parthenolecanium corni
Pest description and damage Scale insects are small (less than 0.125 inch in length) soft insects that live beneath waxy scales. These insects are often identified by the shape and size of their scales, the description of adult males and females, immature crawler stage, color of eggs, and host plant preferences. Lecanium scales are most noticed as the females expand in size in the spring. As females swell in the spring, they produce large egg masses under their scales and release considerable honeydew that coats nearby foliage. The female lecanium scales are about 0.13 inch in diameter and vary from reddish-brown to dark brown in color. The adults are oval and raised, resembling small "helmets," "turtles," or bumps on branches and stems. Male scales are smaller, flat, and oblong. Pale yellow crawlers feed mostly on the underside of leaves.
For biology, life history, monitoring and management
See:
Ash (Fraxinus)-San Jose scale
See "Scale insect" in:
Management-chemical control
See Table 1 in: