4 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 
the vines, although little foliage may have fallen from the vines by 
that time. During the entire month of October a general dispersion 
of the adults is in progress throughout the infested area. This disper- 
sion is apparently quite aimless, the individuals settling down and 
collecting wherever sufficient shelter in the form of fallen leaves, sod 
lands, hedges, woodlots, and swales is adjacent to the vineyards. 
Large numbers of them probably never leave the vineyards, passing 
the winter under the protection afforded by fallen leaves, clumps of 
grass, weeds, and cover crops. After leaving the grapevines they 
feed to some ex- 
tent upon the still 
green grass, weeds, 
and cover crops, 
and become more 
or less active when 
disturbed during 
the warmer days 
of winter. 
SPRING EMERGENCE 
OF ADULTS. 
Early in May, 
as the days be- 
come warmer and 
plants commence 
to throw out new 
growth, the adults 
leave their winter 
protection and 
feed somewhat. in- 
discriminately 
Fic. 4.—Grape leaf in early stages of attack by the grape leaf- Upon the new 
hopper, showing the characteristic mottling of the upper sur- growth of almost 
face. (Original.) iF ‘ 
any plant with 
which they come in contact, showing some preference, however, for 
the foliage of bush fruits such as wild blackberries, cultivated rasp- 
berries, and strawberries. This promiscuous feeding terminates with 
the unfolding of the leaves of the grapevine and there is a general 
migration of the insect back to the foliage of the grapevine, this being 
the only plant upon which this particular species of leafhopper is 
known to reproduce. 
The adult “ hoppers” first attack the foliage or sprouts springing 
from the base of the vine or from canes near the lower wire of the 
trellis. When the adult insects are very numerous, sufficient injury 
