Hampshire, New York, and Vermont. Probably it will eventually be found in most 
areas where there are natural stands of sugar maple. 
The European elm scale, Gossyparia spuria (Modeer), apparently was intro- 
duced from Europe. In the United States it is reported from 33 States and probably 
occurs wherever elms are grown. It feeds on native and introduced species of elm 
and is found in natural habitats and ornamental plantings. Adult females are brown 
or greenish brown soon after they molt, but as the adults age, the body turns gray. A 
felted, waxy sack covers the bottom and lateral areas of the insect, leaving only the 
top center of the scale exposed. The first instar is yellow, and the second instar is 
reddish brown. 
The European elm scale has one generation per year and has long-winged and 
short-winged adult males. The second-instar males and females overwinter in 
crevices on the bark of the host. In January, February, and March, the second-instar 
males molt to the prepupa, pupa, and adult. Mature males are most abundant in 
early spring. Molting of second-instar females to the adult stage is coincident with 
seed development of the elm host. After molting, the adult females move to the 
main branches, where mating takes place. When the elm seeds begin to fall, the 
adult females begin to form the characteristic waxy sacks. Egg laying begins 2 or 3 
weeks after the first elm leaves are fully formed and continues into late summer. An 
individual female may lay as many as 400 eggs. The eggs normally hatch within an 
hour of deposition in the ovisac. Crawlers usually move to the undersides of leaves 
and feed near the primary veins. A small number of crawlers feed on the stems of 
the host. About 6 weeks after hatching, the crawlers molt to the second instar. Most 
of the second instars migrate from the leaves to the overwintering sites when the 
leaves begin to turn yellow. The European elm scale is frequently injurious, 
especially to young or recently transplanted elms. Symptoms include stunting of 
new growth, dieback of branches, premature leaf drop, and in small trees, death. 
Sooty mold grows on the large quantities of honeydew produced by this insect and 
gives the infested tree and surrounding objects an unsightly black, sticky ap- 
pearance. Chemical control is frequently effective. Several species of chalcidoid 
wasps, lady beetles, and a green lacewing have been reported as natural enemies. 
The azalea bark scale, Eriococcus azaleae Comstock, is apparently an Old 
World introduction. In the United States, it is reported from 34 States and probably 
occurs wherever azaleas are grown. Although normally found on azaleas, this 
species 1s also reported on willow, poplar, maple, hackberry, fremontia, huckle- 
berry, pieris, rhododendron, gooseberry, and blueberry. It occurs on native and 
introduced hosts and is found in natural habitats and ornamental plantings. Adult 
females are bright red and are covered with many crystalline rods. A tough, pear- 
shaped ovisac is produced that encloses the adult female and the reddish-purple 
eggs. The first and second instars are purple or red. 
The azalea bark scale has one generation per year in the North and two in the 
South. In northern areas the species overwinters as eggs or crawlers in the ovisac. 
The crawlers escape through a small hole at the posterior end of the ovisac and 
settle in branch cr leaf axils. Second instars appear in early summer, and adults are 
prevalent in August. An individual female may lay as many as 250 eggs. In the 
South, the overwintering stage is the settled crawler or second instar. Adult females 
appear in early spring and lay their eggs in March or April. Adult females of the 
second generation mature in late summer and lay their eggs, which hatch in the fall. 
The scale causes dieback and gives heavily infested plants a leggy appearance. 
Chemical control is possible. A chalcidoid wasp, Coccophagus immaculatus 
Howard, often parasitizes this species. 
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