22 



the "hoppers" are notably less abundant than where this practice is 

 not followed. The absence of suitable hibernation quarters in the 



vineyard causes them, largely, to migrate elsewhere, and vineyards 



are much 

 spring and summer. 



receiving such care are much less seriously infested the following 



The grape leaf-hopper secures its food by sucking juices from the 

 interior of the leaf, and arsenical poisons useful against the grape root- 

 worm and the grape berry moth are quite useless against this pest. 



GRAPE LEAF-FOLDER. 



Observing grape growers have often noticed, especially during 

 midsummer and later, grape leaves folded together, the interior 

 (upper) surface of the leal being more or less skeletonized, and within 

 the fold a slender larva, which, upon being disturbed, is apt to wriggle 

 out and fall or hang suspended b}^ a thread. This insect, the grape 

 leaf-folder (Desmin J'uneralis Hiibner; see fig. 7), is widely distributed 



and a few are to be found in 

 vineyards almost every year, 

 while here and there through- 

 out their range they may be so 

 abundant as to do serious in- 

 jury. There are two broods 

 each year in the more northern 

 States and three or possibly 

 more in the South. The insect 

 wintei's in the pupal stage in 

 the folded and fallen leaves, 

 the moths appearing in the 

 spring shortly after the foliage 

 puts out, and the eggs are 

 placed in small patches here 

 and there on the vine. Upon 

 hatching, the young larvae at- 

 tack the foliage, folding the 

 leaves as stated. Mr. Johnson 

 has observed that larvae of the 

 first brood may attack bunches of grape blossoms and young fruit in 

 a way similar to the grape berry moth. In 3 or 4 weeks the larvas 

 are full grown and transform to pupae within the folded leaves, moths 

 emerging some 8 or 10 days later. By midsummer and fall the 

 insects may become quite abundant, and in badly infested vineyards 

 the folded leaves are everywhere in evidence and are quite conspicu- 

 ous from the color of the lower surface. In the fall the larvae pupate 

 in the folded leaves and pass the winter in these on the ground. 



Treatment. 



Where the insects are but moderately abundant it will be quite 

 practicable to search out the folded leaves and crush between the 

 hands the larvae or pupae within. The destruction of the first brood 

 in this way would greatly reduce the number of the insects later in the 

 season. 



284 



Fig. 7.— Grape leaf- folder {Desmia funeraUs) : a, Male 

 moth and enlarged antenna ol same; b, fema'e 

 moth; c, larva; d, head and thoracic segments of 

 same, enlarged; c, pupa; /, tip of pupa, enlarged; 

 g, grape leaf folded hy larva. (From Marlatt.) 



