Note 103 — Chapter III · THE VITICULTURE OF NEW YORK

Grape leaf-hopper (Typhlocyba comes Say).—There are several species of leaf-hoppers which attack the grape but this species is probably the most common in this State. These little leaf-hoppers are often erroneously called thrips. The adult insects measure about one-eighth of an inch in length. They vary greatly in color but the prevailing color is usually light yellowish-green. The back and wings are ornamented with bright red, yellow and brown. They are found upon the vines from spring until fall. They feed together, sucking the sap from the leaves, principally from the under surface, causing them to turn brown in patches. The eggs are deposited singly in the tissue of the under surface of the leaves. The young resemble the adults in form but are not provided with wings and are green or yellowish-green in color. There are several broods during the season. Some of the adults of the last brood hibernate in any convenient rubbish about the vineyard. Treatment for young hoppers should be made early in July. To obtain the best results use whale-oil soap at the rate of one pound to ten gallons of water, directing the spraying with the hand. Vineyards and adjacent land should be kept as free as possible from grass and weeds as they afford shelter to the insect.