GRAPE PESTS AND THEIR CONTROL 217 



Still another pest found throughout the United States and 

 especially destructive in California is the hawk-moth (Pholus 

 achemon), the larvae of which occasionally do serious damage 

 to small areas of vines. These larvae are very similar to the 

 large worms, familiar to all, which attack the tomato and 

 tobacco. The insect hibernates in the pupal state in the 

 ground where it may be distinguished as a large cylindrical 

 object of dark brown color. The moths emerge about the 

 middle of May and deposit their eggs on the leaves of the grape, 

 upon which the larvae when hatched immediately begin to 

 feed. There are several species of these hawk-moths, all of 

 which have essentially the same life history. It is not a diffi- 

 cult pest to control since the larvae are easily killed with arseni- 

 cal sprays ; or if there are but occasional specimens they may 

 be picked by hand. There are several species of the hawk- 

 moth which attack the grape but this is the common one. 



In eastern grape-growing regions, there are two other destruc- 

 tive grape insects widely distributed, but each noteworthy as 

 pests only in the Appalachian region of West Virginia and 

 neighboring states. One is the grape-curculio (Craponius 

 incequalis), not essentially different from the familiar curculio 

 of the plum and cherry. This snout-beetle feeds freely on the 

 upper surface of the leaves and the bark of fruit stems, and the 

 female in laying eggs devours the tissues of the grapes in ex- 

 cavating her egg chamber. The grape-curculio is effectively 

 destroyed by spraying with an arsenical spray in the spring 

 as the beetles appear on the vines and before egg-laying begins. 



Another insect pest of this region is the grape-vine root-borer 

 (Memythrus polistiformis) closely allied ''to the peach-borer, 

 known by all fruit-growers and the squash-vine borer known 

 to the growers of vegetables. This borer is the larva of a 

 moth and is a whitish grub with a brown head which, when 

 fully grown, is about one and three-quarters inches in length. 

 The body is slender, distinctly segmented and has a sparse 



