4 Farmers’ Bulletin 1225. 
The eggs (fig. 2, A) are tiny and transparent and are laid in the 
tissue of the potato leaf. The eggs can not be seen from the out- 
side, but after they hatch the leaf tissue dies and forms small, sunken 
pits marking the pe ake location of the eggs. 
The nymphs (fig. 2, B-F), or young leathoppers, pass through 
several stages of growth and shed their skins several times, develop- 
ing wings in the adult stage. When newly hatched, the nymphs 
are very small and nearly white, but slowly turn green as they erow. 
When the insect is nearly mature, the partially = eloped wings may 
be seen on each side of the body, and the ‘‘hopper’’ at this stage is 
quite active, being able to hop from leaf to leaf. 
DISTRIBUTION. 
The potato leafhopper occurs in practically every State of the 
Union and in parts of Canada and Mexico. Its greatest dimage to 
potatoes has occurred in the Northern and Cay States, noun 
from Montana to New York and south to Ohio, Illinois, and Kansas. 
ECONOMIC IMPORTANCE. 
The economic loss to the potato grower caused by the attack of the 
potato leafhopper and the accompanying ‘“‘hopperburn’’ is said to 
be second only to that caused by the Colorado potato beetle. In 
years when the leafhopper and “hopperburn’’ are abundant the 
combined loss may take first place in some regions among all potato 
insects and diseases. It is, therefore, essential that the grower 
become familiar with the insect, with the nature of its injury, and 
with measures for its control when a serious outbreak occurs. 
SEASONAL HISTORY. 
The potato leafhopper lives over winter in the adult stage, hidden 
away in brush heaps, matted weeds, and other protected places. 
Some time during May the leafhoppers emerge from their winter 
quarters, feed for a week or so on various trees and shrubs, then 
suddenly migrate to potatoes and beans where mating and egg laying 
begin. There are two generations of the insect in the Northern 
States with three, four, or perhaps five generations in the Central 
and Southern States. 
Under Wisconsin conditions the adults which have lived over 
winter die off during July and their young mature about the last of 
July, forming the first generation. Thus it takes approximately one 
month from othe time the eggs are laid until the adult leafhoppers 
appear. A second generation is now produced, although in a slightly 
shorter time, and the new adults begin to appear about the first of 
September. These adults live over winter and do not lay eggs until 
the next spring. 
