652 



STATE BOARD OF AGRICULTURE. 



are so similar that it seems impossible to differentiate them from the 

 present statements in the literature. 



Jones^ and. Lutman*, who worked on the problem in the east, have 

 , reported that owing to the more severe drought conditions in the 

 middle western states, Michigan, Wisconsin, Minnesota and Iowa, tip- 

 burn caused greater damage in those states than in Vermont. During 

 the three years' investigation of the jjroblem in Michigan, the writer has 

 not been able to find any burning of the tips and margins of potato 

 leaves which he could not associate with the potato leafhopper as the 

 causal factor. If the insect itself was not found upon the leaf, cas^; 

 skins of nymphs, egg pockets, or the eggs themselves were located. 

 There is no doubt that hopperburn is the greatest factor reducing 

 Micliigan ]»otat(» yields and that tipburn, if i>resent at all. is of very 

 minor importance. 



THE POTATO LEAF HOPrER, EMPOASCA MALI LE B 

 DESCRIPTION 



Adults: The adult leafhopper is a very active yellow-green insect about 

 one-eighth of an inch long. It is distinguished from its near neighbor, 

 Empoasca unicolor Gillete and other green leafhopjiers by a row of six 



Fig. 5. Potato leafhopper adults (Empoasca mail LeB.) x G. The white markings seen on the back of the insects arc char; e- 



teristics which identify the potato leafhopper. 



or eight white dots on the anterior margin of the prothorax and by the 

 characteristic "H" marking on the mesothorax. (Fig. 5). The adult 

 female is slightly larger than the male, from which it is distinguished 



