852 EXPERIMENT STATION RECORD. I Vol. 37 



41.6 days in the fall. The number of instars and their length is quite variable, 

 the larvaj molting four or five times in summer and five or six times in the fall. 

 The length of the pupal stage varies from 7 to 11 days in July, 7 to 10 days 

 in August, 8 to 18 days in September and October, and from 9 to 21 days in 

 October and November. The longevity of the adults in rearing cages averaged 



12.7 days for the summer months. 



There are thought to be four generations of this species at Columbia. S. C, 

 three complete generations having been reared from the middle of June to the 

 middle of October in 1913. In the latitude of Columbia the first part of the 

 winter is apparently passed as a larva and the latter part as a pupa and 

 possibly adult, the larva? having been found in the field in their burrows in the 

 stalk-s as late as the middle of November. In Arizona it is thought to pass the 

 winter in the larval stage, since larvae in all .'^izes were found at Tempe as 

 late as November 3. 



The species apparently suffers very little from natural enemies, a single 

 parasite (Neopristomerus sp.) having been reared at Columbia, S. C, and 

 Orgilus Icrviventris at Gainesville, Fla. 



Much can be accomplished in the control of this pe.st through late fall and 

 early winter plowing after the removal or destruction of all remnants and 

 waste material in the field, harrowing of the borders and terraces to break up 

 the winter quarters of pupa?, the use of fertilizer to stimulate plant growth 

 and make the plants more resistant to attacks by the pe.st, and the early plant- 

 ing of corn, sorghum, and allied crops to give the plants in the infested soil 

 a good .start before the insect begins its depredations. 



An annotated bibliography of 27 titles is included. 



Control of the grape-berry moth in the Erie-Chautauqua grape belt, D. 

 ISELY {V. S. Dept. Agr. Bui. 550 (1917), pp. Ji2. pis. 6, figs. 9).— Tliis bulletin, 

 which relates particularly to control measures, is prefaced by a brief account 

 of the economic status and a summary of seasonal history and habits of 

 Polychrosis intcana, based upon observations by the author and his associates 

 at North East. Pa., during the .season.*: of 1014. 1915, and 1916, and the work of 

 Johnson and Hamniar. previously noted (E. S. II., 28, p. 453). 



The work has shown that the pest can be controlled by spraying, and that 

 while other methods will reduce berry-moth infestatiim and some of them can 

 be employed profitably to increa.se the efficiency of spraying, none offers a 

 dependable control in commercial vinoyards. The spray mixture recommended 

 consists of arsenate of lead paste 3 lbs. or powder 1.5 lbs. and resin fish-oil 

 soap 1 lb. in Bordeaux mixture (3:3: 50). In case of extremely heavy infesta- 

 tion the amount of arsenate of lead should be increased to 5 lbs. paste or 2.5 

 lbs. ix)wder, at least in the last application. The spray should be applied with 

 "trailers," the first application immediately after falling of the grape blos.soms 

 and the second applic.ition (about two weeks later) when the grape berries are 

 just touching. The cost of spraying material and labor required to control the 

 grape-berry moth, if applieil to control the berry moth alone, is about $5 per 

 acre, it being assumed that an average of 6 acres are sprayed per day and that 

 150 gal. of liquid are applletl to the acre. 



"The applications of spray materials required for the control of the grape- 

 berry moth are so timed that they may be combined with applications to control 

 the grape rootworm, grape leafhopper, and powdery mildew, and some of the 

 applications for downy mildew and black rot also may be combined with them. 

 Nothing need be added to the spray solution for rootworm control ; nicntin sul- 

 phate (40 per cent) at the rate of 1:1,600 should be added to the second 

 application for leafhopper control ; and Bordeaux mixture should be used in 

 both applications for fungus diseases." 



