148 



A.¥ ECONOMIC ENTOMOLOGY. 



found on grape-vines, which causes the leaves during the latter 

 part of the summer to become marked with brown spots, some- 

 times in such numbers that they become confluent and the entire 

 leaf is ' ' burnt. ' ' If we tap a leaf at this time swarms of little 

 creatures, not exceeding an eighth of an inch in length, prettily 



marking. Many are the crops infested by these little hoppers, 

 and, though there are good characters by which they can be 

 distinguished scientifically, yet to ordinary observation they 

 appear much aHke, except in size and color. 



The methods of preventing injury are much the same for all 

 species. In the first place, where experience has shown that the 

 insects are likely to occur during the summer, all rubbish should 

 be disposed of in the course of the winter preceding. This can 

 be done by collecting and burning, or by plowing under very 

 early and cultivating so as to leave a clean field. Loose bark, 

 dead branches, twigs, or scaly fence-posts should all be attended 

 to, and piles of dead grass or weeds along fences or in corners 

 should be burnt or otherwise destroyed. In this way much can 

 be done to prevent the insects from getting a start. When the 

 larvae are first noticed great success has been attained in vine- 

 yards by walking along the sides of vines strung on wires, dis- 

 turbing them to start the insects, which jump wildly and readily. 

 A shingle or palm- leaf fan smeared on both sides with coal-tar or 

 insect-lime should be kept in constant motion near the vines, and 

 by this fanning a great quantity of the jumping larvae will be drawn 

 to the smeared surfaces and destroyed. This method is practical, 

 and has been found effective within my own experience ; so large 

 a proportion of the insects being captured in the course of two 



The grape-Ieaf-hopper, Erythroneura vitis ; at rest, 

 and with wings expanded. 



Fig. 109. 



marked with green, rosy- 

 red, and yellow, will fly 

 or jump from them. 

 EarHer in the season 

 they are yellow or green- 

 ish, without wings, but 

 jump readily if disturbed. 

 On roses we find a simi- 

 lar appearance, and here 

 the species are green or 

 yellowish, without much 



