18 Farmers’ Bulletin 1220. 
It is entirely practicable to use the nicotine spray on vines growing 
around the home, using the nicotine sulphate at the rate of about one- 
half fluid ounce to each 5 gallons of soapy water. Spraying for the 
leafhopper when the leaves are yellow and brown, as in late summer 
and early fall, will not be profitable. In localities where this pest is 
usually troublesome careful watch should be kept in late spring or 
early summer of the older lower leaves and the spray applied before 
the first-brood nymphs attain wings, as above indicated. The in- 
jurious effect of the grape leafhopper in causing the shedding of the 
leaves is shown in figure 12, and the 
benefits resulting from the control 
of this” pest by the nicotine spray 
are shown in figure 15. The de- 
struction by burning, in the fall 
and early spring, of weeds and 
grasses growing along ditches, 
fences, and hedgerows, or around 
vineyards, will be highly advan- 
. tageous as removing suitable hiber- 
nating quarters of the insect. 
THE GRAPE LEAF-FOLDER.’ 
During midsummer and early 
fall the work of the grape leaf- 
folder is often in evidence on vines 
growing around the home, or in 
vineyards not regularly sprayed 
with arsenicals. The caterpillar 
folds the lower surface of the leaf 
over against the upper surface 
(fig. 16) and when they are abun- 
dant the lighter color of the lower 
leaf surface readily indicates their 
presence, even though the observer 
is some clistance from the vines. Within the folded leaf the active 
slender larva feeds upon the interior (upper) surface of the leaf, 
eating out the soft tissues, leaving the veins and veinlets fairly 
well intact. Sometimes the grape blossoms are eaten: by the cater- 
pillars, but this is unusual. This injury causes many of the leaves to 
fall and prevents the proper ripening of the fruit. 
The insect is widely distributed over the United States and a few 
are to be found in vineyards in any locality almost every year. Dur- 
ing some seasons or for a series of years it may be quite abundant 
locally and require treatment. 
Fic. 16.—Injury by grape leaf-folder to 
grape leaf, 
7 Desmia funeralis Hiibner. 
