6 BULLETIN 1252, U. S. DEPARTMENT OF AGRICULTURE. 
to determine the effect of the spraying upon the holding or carrying 
quality of the fruit. The results are shown in Figure 1 and in 
Plate Il, B. 
The amount of brown-rot at harvest time was not large on any of 
the plats, but was greater on the unsprayed plats than on ‘the sprayed. 
The contrast between the sprayed and unsprayed prunes in the hold- 
ing test 1s very striking and shows the value of spraying as a means 
of removing the sources of infection and also as a preventive of 
losses in case of shipment or in delay in harvesting or drying. The 
relatively small amount of brown-rot on the unsprayed trees was 
apparently due in large measure to the reduction in sources of in- 
fection accomplished by spraying the remainder of the orchard, for 
in neighboring unsprayed orchards more than three-fourths of the 
crop was affected with brown-rot at harvest time, and the harvested 
TAGE 
WOT PERCENTAGE Of BRON OT 
rites ROWED TREATHENT 12 BIKES FFTEFR ACV EST- 
Se Se o 72 D 20 £0 20 £2 
HOST OREOYLIGRD 
WX PULTE FLO S ~ 
SIN F-KSHIOUIL S029” 
BOUMLD LIME SULT HA 
AS LOU FSU SY 
LIME SULS Hike 47° 3O 
WN SPRAYED 
SECOND CLOEYLILD 
MATURE PLUS 
BORDLEALK 
ROSDNATSHCUL SCOP” 
BOMLLDP LIME S/S tle 
CS ROS SISAL SIP 
LIBDE SULSVIINC / 7? SO 
YLNSPRAIVFED 
Fic. 1.—The effect of spraying upon the development of brown-rot on Italian Prunes 
in the orchard and after harvest; experiments of 1915. The trees of the first 
orchard were 24 years old and those of the second were 15. 
fruit was scarcely in a usable condition if allowed to stand over 
night at the drier. 
SPRAYING EXPERIMENTS IN 1916. 
In the 1916 experiments the same sprays were used as in 1915, 
and in addition to the spraying program plats at Felida, Wash., 
were treated with 50-50 sulphur-dust mixture (50 pounds of sulphur 
dust and 50 pounds of hydrated lime). In the second and third 
applications 10 pounds of the hydrated lime in the dust mixture 
were replaced by powdered arsenate of lead for the control of the 
syneta leaf-beetle, and 1 pound of arsenate of lead powder was 
also added to each 50 gallons of spray material. Applications were 
made in the orchard at Felida on April 8 to 12, April 25 to 27, May 
30, and August 30, and in the orchard at Salem, Oreg., on April 1, 
April 21, and June 16. The first application was made just before 
blooming in each case, the second just after the blossoms had fallen, 
the third when the husks had been shed, and the fourth as the fruit 
