BORDEAUX-OIL EMULSION 
11 
teniber 1, 1918, the number had reached a common level for the 
various plats, due to the effects of the entomogenous fungi. 
On May 16, 1918, there were a few red spiders where Bordeaux-oil 
emulsion^ had been applied. They were abundant where simple 
Bordeaux mixture had been used, but very scarce on the unsprayed 
trees. 
GROVE B, WINTER PARK, FLA. 
1918 TREATMENTS. 
A grapefruit grove at Winter Park was sprayed experimentally 
on March 7 and again on April 15 for the control of citrus scab. A 
number of spray materials and combinations were tested, among 
them ammoniacal solution of copper carbonate. Burgundy mixture, 
Elain Bordeaux mixture, Bordeaux-oil emulsion, Bordeaux-resin- 
shoil soap, and several sulphur solutions. Soft shallow-well water 
was used, and the applications were made in the bloom and on very 
young fruit. Scab did not develop in this grove during the summer, 
even on the unsprayed checks, nor was spray injury observed. 
On July 17 scale insects had become very abundant where plain 
3-4-50 Bordeaux mixture had been used; where a 1-1-50 Bordeaux 
mixture had been used there were fewer of these insects than where 
the full-strength material had been applied. Where Burgundy 
mixture and ammoniacal solution of copper carbonate had been 
used there were still fewer scale insects. The plat which received 
Bordeaux mixture plus one-third of 1 per cent of oil emulsion had 
not more than one-tenth as many scale insects as where plain Bor- 
deaux mixture liad been applied. The spray with this proportion 
of oil was very much more effective than Bordeaux mixture contain- 
ing 2 pounds of resin-fishoil soap to each 50 gallons of spray. 
Since the scale insects were quite abundant at this time on certain 
plats, those requiring treatment were sprayed with 1 per cent of oil 
as emulsion on July 23 and 24. Examinations made August 10 
and September 26 showed that this July spraying with 1 per cent of 
oil gave excellent scale control except where plain Bordeaux mixture 
had been applied at full strength. On this plat a second application 
of straight oil emulsion was required. 
A summary of the results relating to the development of rust 
mites is given in Table 3. 
Table 3. — Number of rust mites per square incha on plats receiving copper-spray com- 
pounds compared with those receiving sulphur sprays and the unsprayed check plats 
in 1918. 
Number of rust mites. 
Sulphur sprays. 
Date of examination. 
Copper sprays. 
Check 
Average 
Total. per square 
inch. 
Total. 
Aver age - 
per square 
inch. 
(average 
per square 
inch). 
Mar 14 
4 
5,184 
11, 477 
75.2 
139. 08 
48.8 
June 5 
180 1.088 
15.0 
a Phyllocoptes olekoTws Ashmead. 
