THE GRAPE-BERRY MOTH. 



59 



Table XXV. — Progress of infestation of fruit by larvae of the grape-berry moth in experi- 

 mental plats. Vineyard of Mr. W.S. Wheeler, North East, Pa., 1908— Continued. 



SECOND COUNT OF INFESTED BERRIES, MADE ON SEPTEMBER 24 TO 26. 



Plat No. 



Date of spray application. 



Spray formula. 



Number 

 of appli- 

 cations. 



Number 

 of vines 

 exam- 

 ined. 



Number 

 of in- 

 fested 



berries. 



I 



TiiTiP A. is . 



5-5-3-2-50... 



2 

 3 

 2 

 1 



25 

 25 

 25 

 25 



1,855 



if ! Tim a 4 18 1Q- Tnlv fi 



5-5-3-2-50 



1,440 



III 



IV 



July 6 



5-5-3-2-50... 



1,095 





5_5_3_2-50 



960 











FIRST COUNT OF INFESTED BERRIES MADE ON AUGUST 3, 4. 



V a b 





None 



do: . 



None". 

 None. 

 None. 

 None. 



25 

 25 

 25 

 25 



387 



Do 



do 



198 



Do 



do 



...do.... 



153 



Do 



do 



do. 



67 











SECOND COUNT OF INFESTED BERRIES, MADE ON SEPTEMBER 24 TO 26. 



V a-b 





None 



do 



None. 

 None. 

 None. 

 None. 



25 

 25 

 25 

 25 



4,495 



Do... 



.. do 



2,899 



Do 



do 



...do 



2.466 



Do 



do.... 



do 



1.588 











When the fruit was harvested the crop from the sprayed and from 

 the unsprayed plats was weighed. Table XXVI, in the columns 

 under "Yield in pounds of fruit per acre," shows the difference in 

 crop yield per acre on the sprayed and the unsprayed plats. The 

 last column also shows the cash value of the increased yield per acre 

 on the sprayed vines. 



Table XXVI. — Amount of fruit infested by the grape-berry moth on sprayed and unsprayed 

 plats and cash value of spray benefit per acre. Vineyard of Mr. W. S. Wheeler, North 

 East, Pa., 1908. 



Plat No. 



Date of spray ap- 

 plications. 



Number 

 of appli- 

 cations. 



Spray formula. 



Average 

 number 

 of ber- 

 ries per 

 cluster. 



Total 

 number 

 of clus- 

 ters. 



Number 

 of vines 



ex- 

 amined. 



I 



Va-Vb 

 II 



Va-Vb 

 III.... 

 Va-\1) 

 IV.... 

 Va-Vb 



June 4, June 18 — 



Unsprayed 



June 4, June 18, 

 July 6. 



Unsprayed 



June 19, July 6.... 



Unsprayed 



June 19 



Unsprayed 



5-5-3-2-50. 



5-5-3-2-50. 



5-5-3-2-50. 



2,312 

 3,858 

 3,374 



2,294 

 2,235 

 1,914 

 1,751 

 1,796 



Plat No. 



Total 

 number 

 of ber- 

 ries. 



Total 



number 



of wormy 



berries. 



Per cent 



Date of 



of wormy 



exami- 



berries. 



nation. 



5.3 



Sept. 26 



11.6 



...do 



4.4 



...do 



9.2 



...do 



3.2 



...do 



9.8 



...do 



3.6 



...do 



6.3 



...do 



Yield in pounds of 

 fruit per acre. 



Cash gain in 

 yield of fruit 



on sprayed 

 plats per acre 



(at 1§ cents 

 per pound). 



I 



Va-M) 



II 



Va-Vb 



III 



Va-Vb 



IV 



Va-Vb 



83,232 



102.888 



85,464 



82, 584 



80,460 



68,904 



63,136 



64, 656 



4.452 



3^458 

 7,733 

 2,632 

 6,577 

 2,309 

 4,136 



§12.42 

 12.42 

 14.08 

 10.96 



