PICKERING SPRAYS. 29 
sprayer as a fine mist (Yineland, N. J.) about one-half as much cop- 
per in proportion to that used in the spray adhered to the leaves as 
when standard Bordeaux was used. When the Pickering sprays 
were applied with a hand pump (Vienna, Va.), the ratio of copper 
retained on the leaves was still further reduced in the case of the 
Pickering sprays. 
The use of rosin-fish-oil soap with one of the Pickering sprays 
proved advantageous in the Virginia tests, but not in the New Jersey 
tests. 
Apparently the copper of the Pickering sprays exists in a more 
active and available form than the copper of the Bordeaux spray, as 
evidenced by the severe burning of the grape leaves. No differences 
were detected in the caustic action or in the adhesive properties of 
the Pickering (A) and (C) sprays. The caustic action and the fungi- 
cidal properties of the sprays made by the two formulas were 
apparently the same. 
The Pickering sprays seem to be too caustic for spraying grapes. 
These sprays, however, may have a very definite use for the last 
application when this must be made late in the season after the 
berries are half grown. Bordeaux spray applied late in the season 
tends to remain on the berries, which is undesirable. Pickering 
sprays, however, are nonstaining. 
APPLES. 
Control of Fungous Diseases. 
An orchard of Yellow Newtown (Albemarle Pippin) trees at Green- 
wood, Va., where bitter rot is prevalent, was selected for these 
experiments. The orchard was not well cultivated and was famous 
as a place for bitter rot. 
in 1916. 
Of the 27 trees in the orchard 12 were sprayed with Pickering 
sprays, 12 with standard Bordeaux, 4-5-50, and three were left un- 
spra} T ed. The sprays were applied three times, June 23, July 13, and 
July 27. The Bordeaux spray was applied with a power sprayer 
each time. The Pickering sprays were applied the first time with a 
hand-pump sprayer and afterwards with a power sprayer The 
results of this work are shown in Table 10. 
