age to shade trees, especially elm, is often severe. Small branches 
are sometimes killed and weakened trees become subject to attack 
by various species of boring insects or bark beetles. 
The Fletcher scale, Lecanium fletcheri Ckll., is widely dis- 
tributed in eastern and midwestern United States and Canada. 
Heavy infestations have been observed on Taxus, juniper, and 
arborvitae in nurseries in Ohio, Indiana, and Connecticut, and on 
arborvitae in North Dakota. Because of its prevalence on and in- 
jury to Taxus, it is sometimes called the taxus lecanium. Eggs are 
laid in late May and hatch by early July. Adult females are light 
yellowish-brown, almost globular, and about 3 to 5 mm. in di- 
ameter. Foliage on the inner portions of heavily infested plants 
is often blackened by the sooty mold growing on the honeydew 
excreted by the scales. The oak lecanium, L. quercifex Fitch, at- 
tacks many species of oaks throughout the Eastern States and 
southern Canada. L. caryae Fitch occurs commonly on beech, 
birch, hickory, elm, oak, willow, and walnut. This is one of the 
largest members of the genus—mature specimens are up to 12 
mm. long. L. quercitronis Fitch is occasionally abundant on oaks 
in the South. 
The spruce bud scale, Physokermes piceae (Schr.), feeds on 
Norway spruce in the Northeastern States and southern Canada. 
Mature scales are about 3 mm. in diameter and usually occur in 
clusters of 3 to 5 at the bases of branchlets. The body is reddish- 
brown with irregular flecks of yellow, and is covered with a deli- 
cate coating of powdery wax. The winter is spent as immature in- 
dividuals clustered about terminal buds and there is one generation 
per year. Heavily infested trees are weakened and rendered un- 
sightly by black mold developing in the honeydew which the scale 
excretes. 
Pseudophilippia quaintancit Ckll., the woolly pine scale, feeds 
on young trees of several species of pines from New England to 
Florida and Louisiana. It forms white, wooly masses at the base 
of needles of new growth (240). 
FAMILY DIASPIDIDAE 
ARMORED SCALES 
The family Diaspididae contains more than one-half of all 
species of scale insects. Members of the family live under scales 
composed of cast skins of earlier stages held together by waxy 
excretions of the insects. The terminal segments of the body are 
fused and strongly chitinized. Adult females are small, flattened, 
disclike, and legless. The scale coverings vary from long and 
threadlike, to oyster shape, to circular. The females of some 
species lay eggs; others give birth to living young. Adult males 
and their scale covers are usually elongated. Various trees and 
shrubs are the principal hosts. Kosztarab (436) discussed the 
species occurring in Ohio. 
The San Jose scale, Quadraspidiotus (= Aspidiotus) perniciosus 
(Comstock), a probable introduction from China, was first re- 
corded in North America at San Jose, California in 1880. In 1893 
it was also found in Virginia. It now occurs throughout the United 
States and southern Canada. Its hosts include a wide variety of 
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