522 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



woods, along ditches or fences, etc. They emerge about May 1 

 in New York and at first feed on whatever succulent foliage may 

 be available. By the time the grape foliage appears they have 

 mostly emerged and infest the vineyards. These hibernating 

 hoppers feed and breed on the lower leaves, disappearing about the 

 time the first young become adult. After a few weeks the females 

 commence egg-laying, which continues for about two months. 

 The eggs are laid just beneath the surface of the leaf in groups 

 of from six to nine, or singly, and as they are but one-thirty-fifth 

 inch long and almost transparent, they are scarcely visible save 

 for the eyes of the embryonic nymphs. The eggs hatch in nine to 

 fourteen days. The young nymphs feed like the adults, at first 

 on the lower leaves, but soon spread to all parts of the plant. 

 In New York they become grown in thirty to thirty-five days, 

 and there is but one full generation a year, with a partial second 

 generation, most of the individuals of which probably do not 

 mature before frost. Feeding continues until cool weather, when 

 the adults enter hibernation. In Colorado, New Mexico and 

 California and probably throughout the South, there are two full 

 generations a year. In California, according to Quayle, the 

 nymphs from eggs laid by the hibernating hoppers appear by the 

 middle of May and the following generation of nymphs about 

 the middle of July. 



Control. Cleaning up all fallen leaves and trash in the vine- 

 yard during the winter, or plowing it under in the early spring, 

 will reduce the nuniber of hibernating hoppers, and it has been 

 observed that they are much less numerous in vineyards where 

 clean culture is practiced. The burning over of adjacent meadows, 

 wood lots and fence rows will also be advisable where practicable. 



In California, where the vines are not trellised, a hopper-cage, 

 which has been fully described by Quayle, I.e., is successfully 

 used for catching the hoppers before they commence to oviposit 

 in the spring. In the East this could not be used, and Professor 

 Slingerland has shown that the hibernated hoppers may be caught 

 on sticky shields before they oviposit. " A light wooden frame 

 is made 7 or 8 feet long by 4 feet high. To the crosspiece at the 



