57 



LEAF-HOPPERS. 



Numerous species of leaf -hoppers, insects which obtain their food 

 b}" suction in the same manner as plant-lice, are nearl}- alwaj's to be 

 found on sugar beet and similar vegetables. None <tf these, however, 

 appears to be restricted to vegetables for food, but usually develop 

 on grasses, although occasionallv also on other plants. As a rule, in 

 their earlier stages they exhibit a decided limitation to the food plant 

 on which they began breeding; but as the}" near the more mature 

 stages the}" assume the habit of feeding more indiscriminately. 

 Considerable divergence is exhibited in regard to life histories; but 

 since these insects are, as a rule, not particularly destructive to beets, 

 further discussion of this general problem may be omitted. 



THE CURRANT LEAF-HOPPER. 



{Emj)oasca mall Le B. ) 



This leaf -hopper is described by Messrs. Forbes and Hart as " proba- 

 bly our worst all-round leaf -hopper pest, so excessively abundant that 

 notwithstanding its varied diet it is able to make a serious attack on 

 quite a number of the cultivated plants on its list." It has been found 

 in extreme abundance on sugar beet everywhere in Illinois, both as 

 nymph and adult, showing its ability to breed on 

 this plant. It also attacks beans, cowpea, potato, 

 celery, and corn, and various fruits, as well as shade 

 and forest trees. It is a tiny insect, pale green in 

 all stages, and is apt to be confused with related 

 species. The row of six (sometimes eight) white 

 dots along the anterior margin of the prothorax 

 distinguishes it from others. 



THE FL.AVESCENT LEAF-HOPPER. 



{Empoasca fltwescens Fav. ) 



Fig. f>b.—Einpoasca fla- 

 ■j'fscens— highly magni- 

 fled (original, Division 

 of Entomology). 



Very similar to the preceding in appearance, size, 

 habits, and distribution is the above-mentioned spe- 

 cies (fig. 55). It is sometimes even more abundant. 

 It is paler, nearly white, and has only three spots on the margin of 

 the thorax. 



REMEDIES, 



As a result of studies of the life economy of leaf-hoppers, it has 

 been ascertained that simply cutting the grass and perhaps some other 

 plants affected, and leaving it in the field, will prevent eggs from 

 hatching; the drying of the stems results in the crushing and distor- 

 tion of the eggs, owing to the shrinkage of the plant tissues and the 

 curling of the edges of the sheaths. 



