Tarnished Plant-bug 

 Leaf-hoppers Sugar Beet Leaf -hopper 



The second stage differs from the first in that the nymphs are about 

 twice as large and have two pairs of dark spots on the thorax. 



These spots become more distinct in the third stage and the wings 

 are represented by two small pads on the back margin of the thorax. 



In the fourth stage the wing pads reach nearly half way down the 

 back and the four dark spots become quite prominent. 



The Adult 



The adults are nearly one quarter of an inch in length. The color 

 ranges from a greenish to a brassy brown. The markings are quite 

 variable. Some individuals are quite prominently marked with black, 

 yellow and red, while others are much more modestly colored, greenish 

 brown predominating. 



LIFE HISTORY 



The adults, as already mentioned, as well as some nymphs in the 

 third and fourth stages, hibernate under any convenient trash or under 

 stones, boards and leaves about fields and waste land. 



The adults emerge during the first warm days of spring, and egg- 

 laying begins soon after emergence. Little seems to be known about 

 the place where the eggs are deposited. In all probability, they are 

 placed within the stems of the plants upon which the adults feed. In 

 the latitude of Northern Colorado the eggs of the first generation are 

 deposited about the last of April and early May. 



About a month is required for the development of a single generation. 

 Therefore, there are probably two or three generations each season. 



The generations overlap to such an extent that nymphs of all stages 

 and adults can be found feeding together during the entire summer. 



NATURAL ENEMIES 



Very little is known regarding the natural enemies of this insect. In 

 all probability it is held in check by predacious and parasitic insects 

 and fungous diseases similar to those attacking the false chinch bug. 



3. LEAF-HOPPERS 



With the exception of the aphids, leaf-hoppers probably exceed in 

 number of individuals all other families of sucking insects attacking 

 cultivated crops. 



Although most leaf-hoppers feed upon grasses, often occurring in 

 meadows in such numbers that it has been estimated that from one- 

 fourth to one-half of all the grass growing annually is destroyed by them, 

 several species seriously damage field crops, vegetables, fruits and shrubs. 



The small cream colored rose leaf-hopper which causes the whitish 

 blotches on the leaves of cultivated and wild roses is familiar to nearly 

 every one and will serve as a typical example of this group of insects, 

 several species of which attack the sugar beet. 



(a) SUGAR BEET LEAF-HOPPER 



(Figs. 5, 6 and 7, Plate VIII, Page 25) 



Few insects attacking the sugar beet cause as large annual losses as 

 this minute leaf-hopper. Fortunately this pest has not appeared to any 



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