New YorK AGRICULTURAL EXPERIMENT STATION. 223 
i PEAR PSYEEA* 
P. J. Parrorvt. 
The extensive winter-killing of pear trees as a result of the 
attacks of the pear psylla last summer has attracted consider- 
able attention to this pest. To meet the demand for informa- 
tion, this brief account of this destructive insect has been pre- 
pared to direct orchardists in the methods by which better pro- 
tection may be given their pear trees. 
SYMPTOMS OF PSYLLA ATTACK. 
The presence of the psylla in injurious numbers upon a tree 
is usually indicated by an abundance of a waterish, sticky 
' liquid, called honey dew, which may be first detected during the 
latter part of May or early in June at the axils of the leaves and 
fruits. This liquid later becomes covered with a black mold, 
which gives the trees a blackish, unsightly appearance. Certain 
ants and flies are very fond of the honey dew, and are often 
attracted by it in numbers to infested trees. The presence of 
these insects upon a pear tree should arose the suspicions of 
a careful observing orchardist and should lead to a close inspec- 
tion of the trees if attack by the psylla has not been apprehended. 
APPEARANCE AND HABITS OF THE PSYLLA. 
The adult is an active four-winged insect, measuring about 
one-tenth of an inch in length. It has been compared to a 
miniature seventeen year locust. A number of broods are pro- 
duced during the summer and the adults which live through the 
winter are quite distinct from the summer adults. They appear 
early in the spring and deposit their eggs in protected places in 
the bark. The eggs hatch in a few days and the little larve or 
nymphs at once commence to suck the juices from the young 
leaves and twigs. A favorite place for the young nymphs is in 
*Reprint of Circular No. 5, New Series. 
