142 MISC. PUBLICATION 657, U. S. DEPT. OF AGRICULTURE 
a coccinellid pr adatom Chilocorus stigma (Say). There are indi- 
cations that heaviest infestations develop in dense stands of beech, 
in stands occupying steep ridges, and in mixed stands containing 
high percentages of beech (Ehrlich 742). 
The beech scale can be controlled by the application of a dormant 
spray of lime-sulfur. However, such measures are probably ap- 
plicable only to ornamental plantings. In the forest a degree of con- 
trol is possible by thinning dense stands and lowering the percentage 
of overmature beech in mixed stands. 
The European elm scale (Gossyparia spuria (Mod.) ), accidentally 
introduced into the United States from Europe in the 1880’s, sometimes 
becomes very destructive, especially to ornamental and street elms. 
It is found over most of southern Canada and the United States wher- 
ever its hosts, most of the native and European elms, grow. The adult 
female is oval, reddish brown, and has a waxy fringe along the body 
margin. Eggs are deposited from spring to midsummer. Upon hatch- 
ing, the nymphs seek places of attachment, and most of them make 
their way to the leaves, while some settle down and feed on twigs or 
small branches. This scale passes the winter in the nymphal stage. 
When present in large numbers, this scale causes yellowing and a 
premature drop of foliage. Although young elms may be killed out- 
right, large trees seldom succumb unless they are so weakened that 
they veld prey to the attacks of bark beetles, fungi, or drought (Her- 
bert 227). During the egg-laying period the females excrete honey- 
dew elich: dropping and sticking to the foliage, may become covered 
with a sooty mold, and produce unsightly conditions. 
Famity PSEUDOCOCCIDAE 
Only one species in this family, the maple phenacoccus (Phena- 
coccus acericola King) is of any importance as a forest or shade-tree 
pest. It is a rather large scale, about 5 mm. long, and is covered with 
a mass of cottony wax, “which may be one-half inch in diameter. Its 
principal host is sugar maple (Ace7 saccharum Marsh), and it is found 
throughout the Northeastern States. 
Famitry ASTEROLECANIIDAE 
In this family of scale insects three or four species belonging to 
the genus Asterolecanium may be destructive to forest or ornamental 
growth. These scales are small, ranging from about 1 to 3 mm. in 
diameter. Most species in the genus produce pits or ringlike galls 
on their host, and often this injury may be used as a means of identify- 
ing the insect. Males have never been found in most of the American 
species. Females are smooth and shiny, light yellowish to brownish 
in color, legless and wingless, and possess microscopic antennae. 
Nymphs are so small as to “be har dly visible to the naked eye. Rus- 
sell (365) published a classification of the genus Asterolecanium, and 
Morrison and Morrison (307) published on the subfamily Asterole- 
caninae. 
The yellow oak scale (Asterolecaniwm luteolum Russell) is a very 
small scale that feeds in shght pits on the undersurface of leaves, in 
pits on smooth bark, and in crevices of rough bark. In the United 
States it has been found only on oak in Pennsylvania. Another species 
also found only in Pennsylvania on oak is A. minus Lindinger. It 
lives in pitsin the bark, The holly scale (A. puteanum Russell) feeds 
