20 DIRECTOR’S REPORT OF THE 
the proportions of one part to ten or fifteen parts of water makes 
their use almost prohibitive for commercial orchardists who desire 
a safe and comparatively cheap oil spray. 
Apple and pear mites——This bulletin is a preliminary treatise 
upon the Eriophyidae, a group of plant-inhabiting mites of increas- 
ing economic importance, in which special attention is given to the 
species thriving upon the apple and the pear. 
In the study of the mites upon these fruits, five species have 
been recognized, which are Eriophyes malifoliae Parr., Eriophyes 
pyri (Pgst.) Nal., Eriophyres pyri var. variolata Nal., Phyllocoptes 
schlechtendali Nal., and Epitrimerus pyri Nal. With the excep- 
tion of the former, which is new, these species were first recorded 
from Europe. Eriophyes pyri (Pgst.) Nal., known as the leaf 
blister-mite, is the most abundant species and is responsible for 
the conspicuous injuries to the foliage of the apple orchards of 
Ontario, Wayne and Niagara counties. 
The leaf blister mite is a small, vermiform, four-legged creature, 
about one one-hundred-and-twenty-fifth of an inch in length, and 
is hardly visible to the unaided eye. It hibernates in the buds and 
with the maturing of the bud scales seeks the unfolding leaves 
which it punctures, producing light green and redish pimples which 
develop into galls or blisters of a blackish or reddish brown color, 
depending on the kind and variety of fruit. Besides the pear and 
the apple, the mite attacks the serviceberry ((Amelanchier vulgaris 
Monch), the common cotoneaster, (Cotoneaster vulgaris Lindl.), the 
white beam tree (Sorbus aria Crantz), the European mountain ash 
(Sorbus aucuparia I.), and the wild service tree (Sorbus torminalis 
Crantz). e | 
Nursery stock is commonly infested; and when the mite is 
abundant, pear foliage is much discolored, and the young trees may 
be stunted through the destruction of the terminal leaves of the 
new growth. The appearance of the mite for successive years in 
the nursery is due to methods of budding. The experiments to 
control the mite in nurseries are not completed, but it is believed 
that the pest can be eliminated from the nursery by the selection 
of buds from clean stock and by the fumigation of budding sticks. 
In the experiments upon apple trees, comparative tests have been 
made with kerosene oil, miscible oil, kerosene emulsion and sulphur 
