GRAPE PESTS AND THEIR CONTROL 215 



ripe, form cocoons on the leaves and hibernate. The moths 

 are small, brown in color, mottled with gray and so much the 

 color of the grape cane that they can hardly be detected when 

 resting on the wood. 



The grape-berry moth is difficult to control but much can be 

 done to curtail its ravages. Spraying after the fruit sets is the 

 most effective preventive. Bordeaux mixture should be used 

 (4-450) to which has been added one and one-half pounds 

 of resin-fish-oil soap and three pounds arsenate of lead. A 

 second application of the same spray is advisable in early 

 August. In a small vineyard or with a slight infestation, it 

 often pays to pick and destroy the berries infested by the 

 spring brood. Plowing infested vineyards in late fall or early 

 spring to bury all leaves prevents the emergence of many of 

 the moths. To be effective, this practice must cover the 

 leaves deeply directly under the vines and this earth must 

 remain until after the time for the adults to emerge. Plow- 

 ing under leaves is not as effective on sandy as on heavy soils, 

 since sandy soils do not become sufficiently compact to prevent 

 the escape of moths. 



Insect pests of minor importance. 



Of the 200 species of insects that feed more or less on the 

 grape, entomologists mention several others than those described 

 that in occasional years or localities become abundant and 

 cause serious injury. Thus, there are several species of cut- 

 worms which sometimes feed on the expanding buds of the 

 young leaves of grapes. The damage of these cut-worms 

 to the grape is greater in California than in other parts of the 

 United States, but nevertheless they occasionally feed on the 

 vines in eastern regions to the detriment of the crop. The 

 most satisfactory control measure for cut-worms is the appli- 

 cation of poisoned bait placed on the ground at the base of the 

 vines. 



