4 FARMERS’ BULLETIN 737. 
is very probably due to the practice of planting wheat before the 
clover comes up in the spring. In some of the western States it 
has at times been considered a pest to sugar-beet plants. 
As plants of one family constitute the principal food plants of 
this leafhopper, it is to be assumed that it has not the power of 
readily adapting itself to changes of food plants. The fact that 
the clover leafhopper occurs in grass and pasture lands and also 
feeds upon grain plants in the absence of clover or alfalfa during 
the winter and spring merely indicates that when its favorite plants 
are not obtainable it is forced to seek food elsewhere. 
STAGES AND LIFE CYCLE OF THE LEAFHOPPER. 
There are three general stages in the development and growth of 
all leafhoppers, namely, egg, nymph or immature stage, and adult. 
The adult female places her eggs in stems and leaves, these hatching 
in from 5 to 12 days during the summer months in the latitude of 
southern Illinois. The nymphs develop and increase in size by 
shedding their skins ‘through a series of five molts, becoming adults 
after the last molt. The nymphal stage in the same latitude ranges 
from 18 to 55 days, with an average of 25 days. 
NUMBER OF GENERATIONS IN A YEAR. 
The number of generations of the leafhopper produced annually 
in a given locality varies from year to year, depending on weather 
conditions, and it also varies in different latitudes and climates. 
For southern Missouri and northern Arkansas there are usually 
three distinct broods, covering approximately (1) April and May, 
(2) June and July, and (3) August and September. Farther south 
or under subtropical conditions it is probable that there are four 
or more. 
HOW THE LEAFHOPPER PASSES THE WINTER. 
In the Northern States the clover leafhopper hibernates in the 
edult stage, at the base of clumps of grass and weeds and under dried 
leaves and trash. Throughout the Central and Southern States it 
could hardly be said to hibernate; instead, the adults merely keep 
in hiding and under cover during cold weather, coming out on warm 
days to bask in the sun and feed upon such green foliage as can be 
found. In Missouri, for example, the adult insects have been observed 
feeding upon wheat during January and February, but not in any 
abundance. Nymphs can not long survive cold weather, and it is not 
probable that eggs survive over winter. In the extreme Southwest, 
where conditions are radically different, the leafhopper is active 
throughout the entire year. 
