There are two broad
categories of scaled, soft and
hard. Cottony
maple cushion scale belong to the soft bodied type.
Cottony maple
scale over-winters as immature females (nymphs)
on twigs and branches. The females mature when the plant resumes growth
in the spring. They secrete the white, cottony masses beneath which, they
lay 500 or more eggs in late May to early June.
The eggs hatch around the first of July and the young, called
crawlers, move away from the females toward the leaves. The settle on the
underside of a leaf and insert their threadlike mouth parts into the tissue
beneath the major veins.
The males mature in late August and early September, mate with
the immature females and die. In late September, just before leaf drop,
fertilized nymphs migrate from the leaves to the twigs and branches. Only
one generation occurs per year.
Scale insects form a protective covering over themselves for most
of the year while they feed on the sap of plants. Since the insects are
unable to fully digest the sap, they excrete the excess in the form of
a thick, sweet substance called "honeydew." When this material drops on leaves below the insect, a fungus called sooty
mold begins to grow . This will turn leaves and stems black but does not
hurt the plant. It is merely a sign that insects are active on the plant.
