They are now able to % from vine to vine or even from one vine- 

 yard to another. Late in October they seek a shelter for the winter, 

 where they hibernate till the following spring. Leaf-hoppers are 

 very active in their movements, and hop from one leaf to another or 

 run sideways, often passing quickly from one side of a leaf to the 

 other for protection when disturbed. 



NATURE OF THEIR ATTACKS. 



Le!if-hoi)pers do not consume the substance of the leaves, but, 

 forcing their tube-like mouth-parts through the epidermis or skin, 

 suck the sap from the interior. The leaves first indicate the presence 

 of these insects by becoming yellowish or brownish in small spots 

 where the sap has been exhausted. As the insects increase in size 

 and take more sap, these spots grow larger and the whole leaf ap- 

 pears as though scorched, turning brown and even falling off in cases 

 where the hoppers are very abundant. The result is that as the 

 leaves are injured, the growth of the stems is checked, the fruit is 

 stunted or fails to ripen, and if the ravages of these insects are 

 not prevented, the vines become entirely ruined in a few years. 



Some varieties of grapes are especially liable to suffer from the 

 leaf-hoppers, as the Delaware, Clinton, and in general all varieties 

 having thin leaves. The abundance of these insects from year to 

 year seems to depend in a large degree upon the severity of the 

 winter and their ability to obtain protected places for shelter. 



REMEDIES. 



The remedies should vary according to the location of the vines. 

 If they are in graperies, smoking them with tobacco, taking care to 

 prevent the escape of the smoke, has been tried with good results. 

 Similar treatment with Persian Insect Powder poured upon burning 

 coals carried under the vines is also successful. Syringing with 

 strong tobacco-water or soapsuds, dusting with lime, sulphur and lime, 

 hellebore and cayenne pepper have all been recommended but have 

 not yet been tested at this station. 



In vineyards, the treatment is more dificult as the adult insects can 

 fly away, and thus avoid the fumes of tobacco or insect powder. If 

 fumigating be attempted in the field, it should be done several times 

 at intervals of a day or two, and before the hoppers develop their 

 wings, that is, in this state the last of July or the first of August. 

 It is always desirable to destroy these insects early, before they are 

 large enough to greatly affect the vines, and before the energy 



