REMEDIAL MEASURES. 



69 



foliage of the plat sprayed with arsenate of lead. (For results, see 

 Table XXV.) 



Table XXV. — Relative value of arsenite of lime and arsenate of lead as insecticides, as 

 shown by egg depositions at North East, Pa., 1907. 



VINEYARD OF W. S. WHEELER. 



Date of 

 appli- 

 cation. 



Formula. 



Siz 

 Large. 



BOfclUS 



Me- 

 dium. 



ters. 

 Small. 



Total 

 clus- 

 ters. 



Esti- 

 mated 

 num- 

 ber of 

 eggs. 



Num- 

 ber of 

 vines. 



Num- 

 ber of 

 canes. 



Eggs 

 per 

 vme. 



Eggs 



per 



cane. 



Date 

 exam- 

 ined. 



1907. 

 July 8 

 July 27 



Unsprayed 



5-6-2-50-1-1 quart 



Kedzie 



5_5_3_50 



37 



27 

 3 



102 



98 

 14 



151 



132 



47 



290 



257 

 64 



6, 420 



5,610 

 1,040 



25 



25 

 25 



50 



65 

 51 



256.8 



224.4 

 41.6 



128.4 



86.3 

 20.39 



Aug. 14 



Do. 

 Do. 







VINEYARD OF W. E. GRAY. 



July 6 

 July 25 



July 6 

 July 25 



Unsprayed 



Prepared Bor- 

 deaux: 1 qt. 

 arsenite lime, 

 2 qts. fishoil 

 soap, 50 gals, 

 water 



Prepared Bor- 

 deaux: 3 lbs. 

 arsenate of 

 lead, 50 gals, 

 water 



28 



119 



139 



286 



6,360 



25 



75 



254. 4 



84.8 



21 



107 



155 



283 



5,810 



25 



63 



232.4 



92.22 



1 ^^ 



49 



78 



136 



2,800 



25 



58 



112.0 



48.27 



The vines on all these plats were quite thrifty and were carrying 

 a heavy foliage. 



The second experiment for comparing the value of these two poi- 

 sons against the grape root-worm beetle was made on a 12-acre vine- 

 yard belonging to Mr. W. E. Gray, North East, Pa. The vineyard 

 was divided into three plats, 5 acres on the east side, 2 acres 

 through the middle of the block, and 5 acres on the west side. In 

 this experiment a commercial brand of prepared Bordeaux mixture 

 was used. The poison ingredients of the spray, how^ever, were the 

 same as in the experiments on the vineyard of Mr. Wheeler. The 

 plat on the east side of the vineyard was sprayed with a mixture of 

 2 gallons prepared Bordeaux mixture, 1 quart of arsenite of lime, 

 Kedzie formula, 2 quarts of fishoil soap, and 50 gallons of water. 

 The plat on the east side of the vineyard was sprayed with a mixture 

 of 2 gallons of prepared Bordeaux mixture, 3 pounds of arsenate of 

 lead, and 50 gallons of water. The 2 acres through the middle of 

 the vineyard were left unsprayed. As in all of our other spray exper- 

 iments, the foliage in the untreated plat show^ed much more feed- 

 ing by the beetles at the time of taking the records of egg deposition. 

 A greater amount of feeding by the beetles was also apparent on the 

 foliage treated with arsenite of lime than upon that treated with 

 arsenate of lead. The results of these experiments are set forth in 



