INSECT ENEMIES OF EASTERN FORESTS 149 
necessary to dip in a 1-to-12 mixture of lime-sulfur all pine stock 
shipped during the year from the Forest Service Cass Lake Nursery 
in Minnesota. 
There are two species of scales in the genus Chrysomphalus that 
attack forest and shade trees sufficiently to be considered here. Prob- 
ably the most injurious of the two is the gloomy scale ((. tenebri- 
cosus (Comst.)), which is particularly destructive to soft maples in 
the South and also attacks sugar maple, hackberry, elm, and boxelder. 
It is southern in distribution, being recorded from Washington, D. C., 
west to Ohio and south and southwest to Georgia, Tennessee, and 
Texas. 
The gloomy scale somewhat resembles the San Jose scale. Adults 
are gray, but the protruding nipple on the dorsum is usually more con- 
centrically placed than in Aspidiotus perniciosus. Moreover, the inner 
bark of trees infested with this species does not show the red coloration 
that occurs in trees infested with A. perniciosus. Chrysomphalus ten- 
ebricosus was reported by Kotinsky (269, p. 78) as especially abundant 
in the South. 
The obscure scale (Chrysomphalus obscurus (Comst.)) attacks 
pecan, oaks, elm, hickory, and hackberry, and is found over much the 
same territory as the gloomy scale. Heavy attacks may cause small 
limbstodie. It has one generation a year (Baker, 14). 
The elm scurfy scale (Chionaspis americana Johns.) attacks elm 
and hackberry from New England west to [hnois, southwest to Okla- 
homa and Texas, and south to Georgia and Florida. Adult females 
of this species are covered with a dirty-white, oystershell-shaped scale 
about 3 mm. long, the front part of which is frequently covered with 
a grayish or blackish secretion. In the Northern States there are two 
generations a year. Farther south there probably are more. Injury 
consists of the dying of twigs, branches, and small trees in heavy in- 
festations; and, although large trees are not known to be killed, they 
may be so weakened as to be susceptible to injury by other insects. 
The seurfy seale (Chionaspis furfura (Fitch) ) is frequently found 
on elm, ash, aspen, cherry, hickory, maple, black walnut, and willow, 
and is distributed widely over southern Canada and the United States. 
Females of the species are somewhat pear-shaped, about 2 mm. long, 
and under ordinary city conditions are dirty gray. This scale attacks 
the leaves, branches, and main trunk of its hosts. (@. /intnera Comst., 
a closely related species, is found on willow, birch, dogwood, and vari- 
ous other trees and shrubs in the Northeastern States and southeastern 
Canada. 
The euonymus scale (Unaspis euonymi (Comst.)) attacks euony- 
mus, as well as certain other species of plants, and may be found over 
most of the United States wherever its hosts occur. This scale is 
oblong, broadened posteriorly, and varies in color from dirty gray 
through brown to nearly black. In the North there are two genera- 
tionseach year. Heavy infestations (fig. 36) may kill twigs, branches, 
and even entire trees within a few years. 
The pine-needle scale (Phenacaspis pinifoliae (Fitch) ), although 
common throughout the United States and in southern Canada, and 
potentially destructive in ornamental plantings throughout this ex- 
tensive area, is apparently most prevalent east of the Mississippi River. 
It attacks, in addition to the various spruces, the following pines: East- 
