Common name: Magnolia scale
Scientific name: Neolecanium cornuparvum
Hosts: Magnolia scale feeds on magnolia trees. Star magnolia, saucer magnolia, and many magnolia hybrids are most commonly and severely affected.
Scale insects are unique and look quite different from other insects. In their juvenile growth stage, they are referred to as crawlers. As crawlers, they are highly mobile, six-legged, have no protective cover, and are very small (<1/32 inch). At maturity, scale insects are immobile, have a covering over their body and are large enough to see without a magnifying glass.
Scale insects fall into two categories, soft scales and armored scales. Magnolia scale is a soft scale. The soft scales are usually larger than armored scales. They lack a hard, protective cover, instead covering themselves with waxy secretions. Soft scale produce a sticky substance called honeydew; armored scale do not. Magnolia scale is our largest soft scale insect, reaching ½ inch in length. When populations are high, they can cause decline in the health of the host. In addition, the honeydew and the black sooty mold that grows on it, produce a mess on and under the tree.