PICKERING SPRAYS. 41 



Table 13. — Adherence of copper from various sprays to cranberry leaves (New Jersey). 



Plat No. 



Spray used. 



Copper sul- 

 phate in 

 spray used 



Time be- 

 tween 

 spraying 

 and gath- 

 ering. 



Amount of copper. 



Parts per 



million 



(dry basis). 



Parts per 

 million per 

 0.1 percent 

 of copper 

 sulphate 

 in spray. 



1917. 



1 



2 



3 



4 



5 



6 



7 



8 (check). 



2... ...... 



3 



4 



5 



6 



7 



8 (check). 



f 1918. 



1 



2 



4 



5 



6 



7 (check). 



Pickering 

 Pickering 

 do... 

 Pickering 

 Bordeaux 

 Bordeaux 

 Bordeaux 



(A). 

 (C). 



(A) 



,4-3-50.... 

 , 2WJ-50. 

 ,2|-2i-50.. 



Per cent. 



0.32 

 .405 

 .54 

 .64 



1.00 

 .64 

 .64 



Picktring 

 Pickering 

 do... 

 Pickering 

 Bordeaux 

 Bordeaux 

 Bordeaux 



(A). 

 (C). 



(A) 



,4-3-50... 

 2MJ-50. 

 2*-2i-50. 



.32 

 .405 

 .54 

 .64 

 1.00 

 .64 

 .64 



110.8 

 140.2 

 167.2 

 166.2 

 680.2 

 407.8 

 385.4 

 32.6 

 80.0 

 100.7 

 146.7 

 131.3 

 429.0 

 138.0 

 323.4 



7 (check). 



Sal soda and rosin-flsh-oil soap . 

 Sal soda and fish-oil emulsion . . 



Barium water and soap 



Pickering (C ) and soap 



Pickering (A) and soap 



1.0 



1.0 



.6 



Bordeaux, 4-3-50, and soap 



B ordeaux , 4-2-50, and soap 



B ordeaux , 4-1-50, and soap 



Sal soda and rosin-fish-oil soap . 

 Sal soda and fish- oil emulsion . . 



Barium water and soap 



Pickering (C ) and soap 



Pickering (A) and soap 



1.0 



1.0 



1.0 



1.0 



1.0 



.6 



.6 



.6 



Bordeaux, 4-3-50, and soap . 

 Bordeaux, 4-2-50, and soap . 

 Bordeaux, 4-1-50, and soap. 



1.0 

 1.0 

 1.0 



1,200 



1,300 



1,100 



1,100 



1,400 



47 



1,600 



1,S00 



1,600 



330 



380 



210 



630 



370 



17 



840 



1,000 



860 



120 



130 



183.3 



183.3 



233.3 



160 

 180 

 160 



33 



38 



35 

 105 



61.7 



The leaves sprayed with Bordeaux held a higher percentage of 

 copper than those sprayed with the Pickering sprays, indicating that 

 the extra lime of the Bordeaux spray, at least where rosin-fish-oil 

 soap was used, is an important factor in increasing the adhesive 

 properties of the spray on cranberry leaves. Possibly the copper of 

 the Pickering sprays was more efficient as a fungicide per unit of cop- 

 per present in the sprays than that of the standard Bordeaux spray, 

 although the copper of the Pickering sprays did. not adhere to the 

 leaves as well as that of the Bordeaux sprays. The results for control 

 of rot favor this view. The percentage of rotten berries (Table 12) 

 does not speak particularly well for the sprays used on Plats 5 and 7, . 

 in spite of the fact that the leaves receiving these sprays retained 

 the largest amounts of copper (Table 13). The results given in 

 Table 13 show nothing concerning the distribution of the copper on 

 the leaves or the form and efficacy of the copper on the leaves. 



IN 1918. 



One set of sprayed cranberry leaves was gathered for analysis for 

 copper on June 25, directly after the sprays had been applied, and a 



