86 INSECTS INJURIOUS TO VEGETABLES 



As we walk over lawns and through meadows and pastures 

 generally, particularly in midsummer and later, myriads of 

 these minute creatures fly up and are sometimes annoying by 

 getting into our faces and even our eyes. Recently their true 

 economic value has been ascertained, and this was brought 

 about mainly through the studies of Prof. Herbert Osborn, in 

 Iowa. They are most numerous in grasses from which they 

 drain the vitality by sucking the sap from the blades. It has 

 been estimated that between one-fourth and one-half of all the 

 grass growing annually is destroyed by leafhoppers, a startling 

 statement but borne out by actual observation. Although most 

 of these insects feed on grasses, there are some which, partic- 

 ularly in their later stages as nymphs and as adults, attack 

 various vegetables and other plants. Leafhoppers are mostly 

 small, some very minute and slender, with short heads more or 

 less crescent-shaped, and with long hind-legs which fit them for 

 jumping. They also have long wings and are strong flyers. 

 The species illustrated (fig. 48) attacks a variety of vegetables. 



In their attacks on plants the usual method is to puncture the 

 cells from the under side of the leaves, causing yellowish, 

 brownish or other discolored spots to appear later. When 

 punctures are numerous entire leaves wilt and die. A few forms 

 attack culinary vegetables by preference, but most others occur 

 on different plants. No less than thirty distinct species have 

 been found on beets. 



Methods of Control. — Several methods have been devised 

 for keeping leafhoppers in subjection. The standard remedies 

 are kerosene-soap emulsion and sprays of soap. An underspray- 

 ing is always necessary. The spray should be as fine as possible, 

 and applied upon the first appearance of the insects, not only to 

 produce the best effect, but because by using it early in the 

 spring the insects may be prevented from developing in large 

 numbers later in the season, for with many forms there are two 

 and sometimes three generations produced annually. 



