lateral filaments; the caudal pair is about one-eighth as long as the body. An ovisac 
is produced that encloses all but the anterior portion of the adult female. 
The apple mealybug has one generation per year and overwinters as a second 
instar in crevices in the bark. In early spring, the second instars migrate to the 
leaves or new growth of the stems. In late spring and early summer, adults appear, 
mating takes place, and egg laying begins. First instars appear in July and feed 
primarily on the leaves. Second instars migrate from the leaves to the bark in the 
fall. The apple mealybug is an economic pest in apple orchards in Maine, Nova 
Scotia, and British Columbia, and is occasionally a pest of ornamentals such as 
maple, basswood, and cotoneaster. In many areas this mealybug is held to low 
populations by the small wasp Allotropa utilis Muesebeck. Other natural enemies 
include chalcidoid wasps and lady beetles. 
Phenacoccus acericola King, the maple mealybug or maple phenacoccus, is 
probably an introduced species. In the United States it occurs in 16 States from 
Maine to Tennessee and west to Illinois. The preferred host is sugar maple, but it is 
also reported on other species of maple and on buckeye, basswood, and hornbeam. 
The species is normally a pest in ornamental plantings, but is also present in natural 
habitats. The adult female is yellow and is lightly dusted with a flocculent white 
wax. The body margin has 16 to 18 pairs of broad, waxy filaments which are less 
than one-fourth the length of the body. An ovisac encloses all but the anterior end of 
the adult female. 
In Ohio, the maple mealybug has two or three generations per year on sugar 
maple and overwinters in bark crevices as immatures (605). The overwintering 
immatures migrate to leaves of the host and feed in the early spring. In June the 
adult females migrate to the bark and mate. The adult females return to the leaves, 
produce a large ovisac, and lay more than 500 eggs. The ovisacs generally are 
produced on the underside of the leaves near the primary veins. Damage caused by 
the maple mealybug principally detracts from the appearance of the host. Several 
chalcidoid wasp parasites and lady beetle predators have been found associated with 
the maple mealybug. 
Phenacoccus dearnessi King, the twocirculi mealybug, is of uncertain origin; it 
may be a native species. In the East it occurs in Illinois, Indiana, lowa, Kansas, 
Maryland, Missouri, New York, Ohio, Pennsylvania, and Wisconsin; it is also 
reported in five Western States. The species is restricted to rosaceous hosts: 
serviceberry, cotoneaster, hawthorn, quince, and Prunus spp. It is a pest in orna- 
mental plantings, although it is found also in natural habitats. The adult female is 
red and is covered by a thin layer of white wax. The lateral filaments are short and 
inconspicuous or are absent. The ovisac may be absent or restricted to the posterior 
part of the venter. Males are abundant. 
The twocirculi mealybug has one generation per year and overwinters as second 
instars in crevices in the bark. In the spring the females move and begin feeding in 
the crotches of twigs or at the bases of bud scales. Adult females produce living 
young or eggs that hatch within minutes after being laid. First instars settle on the 
leaves and begin feeding. In the summer the crawlers migrate to cracks in the bark 
and go through a summer diapause period. During early fall the crawlers return to 
the leaves, feed, and develop into second instars. In late fall the second instars 
move to the overwintering sites. Heavy populations of the twocirculi mealybug 
cause accumulations of large quantities of honeydew and sooty mold and give the 
host plants an unsightly appearance. Large infestations may cause early leaf drop. 
Natural enemies are not reported for this pest. Normally, chemical control is fairly 
successful. 
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