THE three-banded grape leafhopper and 
OTHER EEAFHOPPERS INJURING GRAPES 1 
By G. A. Runner, Entomologist, and C. I. Buss, Collaborator, Fruit Insect Investiga¬ 
tions, Bureau of Entomology, U. S. Department of Agriculture 
INTRODUCTION 
Studies of the leafhopper fauna on grape, commenced in 1919, have 
reached a stage where a preliminary report seems warranted. A survey 
of the literature shows that all five subfamilies of the Cicadellidae occur¬ 
ring east of the Rocky Mountains have been reported on grape, as follows: 
(1) Bythoscopinae, 1 species; (2) Gyponinae, 1 species; (3) Cicadellinae, 
4 genera, 5 species; (4) Jassinae, 2 genera, 3 species; (5) Typhlocybinae, 
6 genera, 34 forms, mostly distinct species. 
SYSTEMATIC RELATIONSHIPS OF FORMS STUDIED 
Although the writers’ collections extend from the Hudson River Valley 
section to the Lake Michigan grape belt, greatest emphasis has been laid 
upon the Sandusky, Ohio, region. Here most of the hoppers belong to 
the genus Erythroneura. Their systematic relationships within the 
genus are obscure, but an examination of the internal genital apparatus 
in connection with nymphal characteristics promises a solution. So far 
as this work has progressed, the following scheme for the forms in the 
Sandusky region may be tentatively adopted: 
(1) Erythroneura tricincta var. cymbium McAtee: On the whole the most injurious 
and most common form in commercial grape-growing centers west of Cleveland. 
(2) E. comes var. compta McAtee: In large portions of the Lake Erie Island grape 
belt of greater economic importance than tricincta. 
(3) E. comes var. comes Say: The traditional “grape leafhopper,” of importance 
chiefly on the mainland east of Sandusky. 
(4) E. vitifex Fitch: Difficult to separate from comes except by dissection, hence of 
doubtful distribution, although apparently common in the Lake Erie Island region, 
especially on thin-leaved grapes. 
(5) E. vulnerata Fitch: Very widely distributed, but usually unnoticed because of 
its different habits. 
( 6 ) E. ziczac Walsh: Common on thin-leaved grapes throughout the belt. 
(7) E. vitis Harris: Restricted to thin-leaved grapes and dominant on wild Vitis 
vulpina. 
Eight additional forms also occur in the Sandusky region, usually in smaller numbers 
and chiefly on wild grape. 
ECOLOGICAL RELATIONSHIPS 
Detailed studies on the ecological relationships of these forms show 
marked differences in the density and composition of the hopper popula¬ 
tion between different varieties and species of grape and between different 
regions of varying size. These problems will be considered in a special 
paper. 
Erythroneura tricincta var. cymbium , in the regions of its greatest 
abundance, comprises a larger proportion of the hopper population on 
thick-leaved grapes such as Concord and Catawba than on thin-leaved 
grapes such as Delaware, Clinton, and wild Vitis vulpina. Other varieties 
1 Accepted for publication October 2 , 1923. 
Journal of Agricultural Research, 
Washington, D. C. 
aia 
Vol. XXVI, No. p 
Dec. 1, 1923 
Key No. K-117 
