a 
The Putnam scale, Diaspidiotus (=Aspidiotus) ancylus (Put- 
nam), occurs in southern Canada and throughout most of the 
United States. Silver maple and linden seem to be its favored 
hosts, but it also feeds on several other important forest and shade ) 
trees such as elm, ash, hackberry, poplar, dogwood, black locust, 
and beech. Female scales are circular and about 1 to 1.5 mm. in 
diameter. They are dark gray to nearly black and have an off- 
center, brick-red nipple. Otherwise, they closely resemble females 
of the San Jose scale. 
Winter is spent as an immature scale, and growth is resumed 
and completed in the spring. Eggs are laid over a period of sev- 
eral weeks in early summer, and there is one generation per year. 
Ordinarily, this scale is not very injurious; although, it may kill 
small twigs and branches on heavily infested trees. 
Diaspidiotus liquidambaris (Kotinsky) feeds on the leaves, 
twigs, and buds of sweetgum in the South and Midwest. Infesta- 
tions have also been observed on magnolia and red maple. During 
the summer it occurs primarily in pockets on the lower surfaces 
of leaves. Small, discolored galls occur on the upper surface close 
to the pockets. Damage has been serious in nurseries in Missouri. 
D. (=Aspidiotus) aesculi (Johns) has been observed on horse- 
chestnut. 
The hemlock scale, Abgrallaspis (=Aspidiotus) ithacae (Ferris) 
feeds on hemlock, fir, spruce, and pine in Eastern United States. 
It is small, oblong, dark gray or nearly black, and is usually found 
attached to the undersides of needles. The needles of heavily in- 
fested twigs and branches may drop prematurely. The related 
species, A. townsendi (Ckll.), has been observed feeding on 
yellow-poplar. 
The gloomy scale, Melanaspis (=Chrysomphalus) tenebricosa 
(Comstock), occurs from Maryland to Ohio, Florida, and Texas. 
It is often quite destructive of soft maples in the South. Other 
hosts include sugar maples, elm, boxelder, and hackberry. Female 
scales are gray and almost the same color as the bark. They re- 
semble San Jose scales except for their more concentrically placed 
nipples (517). 
The obscure scale, Melanaspis obscura (Comstock) (=Chrys- 
omphalus obscurus), occurs from Massachusetts to Florida and 
Arkansas and feeds on a wide variety of forest and shade trees, 
including oak, maple, elm, hickory, willow, dogwood, hackberry, 
and pecan. Female scales are dark gray to blackish, almost circu- 
lar, and about 3 mm. in diameter. The first exuvium is subcentral, 
nipplelike, and shining black with a white ring. Damage to pecan 
is often serious in the South. Chestnut and white oaks are injured, 
and, in Maryland, willow and pin oaks are severely damaged. 
The elm scurfy scale, Chionaspis americana Johnson feeds on 
elm and hackberry throughout most of Eastern United States. 
Female scales are 2 to 3.2 mm. long, oystershell-shaped, and al- 
most pure white. Twigs, branches, and small trees may be killed 
in heavy infestations, and large trees, seriously weakened. There 
are two generations per year in the North, but in the South there 
are probably more. 
The scurfy scale, Chionaspis furfura (Fitch), feeds on the 
leaves, branches, and trunks of a wide variety of trees in southern 
Canada and the United States. Important forest and shade tree 
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