CITEUS MELANOSE AND ITS CONTROL 
37 
Table 7. — Spraying experiments with 3-.'f-50 Bordeaux-ail emulsion for mela- 
nose control on orange and grapefruit groves at Orlando and Winter Park, 
Fla., in 1920 
Location of grove 
Number of 
applications 
Date applied 
Kind of fruit 
Melanose infection 
Absent 
Infected 
Orlando 
18 weekly 
9 biweekly 
Apr. 1 to Aug. 4 
Apr. 1 to July 22 
do 
Per cent 
99.4 
99.6 
98.5 
6.95 
91.13 
32.43 
92.17 
5.6 
Per cent 
0.6 
Do 
do 
do 
do- 
.4 
Do . 
5 monthly 
Check (unspraved).. 
1.5 
Do 
93.05 
1 
Theck (nnsprayed) 
May 5 to 8 . 
Grapefruit 
. _do 
8 87 
Do 
67.57 
Do 
1 
Check (nnsprayed) 
May 10 to 12 
Oranges 
7.83 
Do 
do.. 
94.4 
The grove at Winter Park, 4 miles from Orlando, was sprayed but 
once for the control of this disease. This application was made 
during the first part of May before much infection had taken place, 
although there had been considerable rain up to that time. From 
2.4- 
2.2 
2.0 
Jb/.<9 
h 
M .* 
.O 
1 
1 
1 
1 
1 L 
■ 
11 
1 
■ 
..i i ii 
miiiiilliil 
Iiiiili In 
I Jl 
ill 
Fig. 5.- 
A^?"&e// 
^ 
^?^/?/l 
/Ws?y 
xyc/A/f: 
-Rainfall (in inches) at Orlando, Fla.. during March, April, May, and 
June, 1920 
the results of this spraying test, together with the results obtained 
by the commercial growers who made tests, it seems that a single 
application of Bordeaux-oil emulsion properly timed should give 
good control of melanose. 
So far as is known this is the first instance where melanose has 
been successfully controlled by a single spray application. 
The results of these tests were made known to the various State 
workers and horticultural advisers for use during 1921, and rather 
large numbers of commercial properties were sprayed that year, 
the material and time of application being based on the results of 
the 1920 tests given above. 
Bain fall during the spring months of 1920. — A graphic record of 
the daily rainfall at Orlando during the melanose season of 1920 
is shown in Figure 5. It is obvious that March of that year at 
Orlando was very dry. No rain fell there during the latter half of 
