12 DEPARTMENT CIRCULAR 409, U. S. DEPT. OF AGRICULTURE 
The period of holding by jobbers, retailers, and consumers is, how- 
ever, very variable, depending on a number of factors, and in some 
instances is quite prolonged. It is in such extreme cases that the 
protection given by the spraying is particularly valuable. Actual 
inspection reports show, in the course of a season, a considerable 
number of cases in which stem-end rot reaches 10 to 20 per cent or 
more at the time cars reach destination. Such fruit was probably 
exposed to considerable infection in the grove, or was subjected 
to unusually high temperatures or to considerable delay in handling, 
or to all of these conditions. Spraying in the grove to guard against 
the first of these contingencies would insure the fruit against much 
of the loss that might otherwise arise from the other two. 
GENERAL DISCUSSION 
The evidence presented shows that the same spray application 
that protects citrus fruits from melanose blemish prevents to a 
considerable degree their decay during marketing. This second bene- 
fit is obtained at no additional cost and is an added reason for 
spraying for melanose.° The various forms of decay are controlled 
in varying degrees, and none of them is entirely eliminated; hence 
the necessity for continuing to observe carefully other precautions 
that have been found to be helpful in preventing decay. Phomopsis 
stem-end rot was reduced in greatest degree, Diplodia stem-end rot 
less completely, and Penicillium blue-mold rot scarcely at all. The 
indications are that potential stem-end rot infection by Phomopsis 
occurs mainly during a limited period which one spraying covers 
rather effectively, while that by Diplodia occurs over a much longer 
period so that a single application of spray results in comparatively 
slight control. 
Notwithstanding the use of oil emulsion in the Bordeaux mixture 
for spraying citrus trees, care must be taken to follow some weeks 
later with a special application of oil emulsion for scale-insect con- 
trol. This would normally be made the last of June or first of July. 
If conditions warrant, an additional application should be made in 
the fall or during a mild period in winter. Proper measures should 
be taken to control rust mites if they appear.’ In other words, in 
planning for the control of one blemish or pest, all others that re- 
quire control should be taken into consideration. Nothing is gained 
by controlling melanose and then allowing the fruit to become 
russeted from rust-mite attack or the trees and fruit to be damaged 
by scale insects or white flies. 
This experimental grove of seedling orange and grapefruit trees, 
about the average of a large acreage in Florida, has improved 
steadily in freedom from pests and in general vigor and produc- 
tiveness during the six seasons of spraying with Bordeaux-oil for 
melanose control. No special ill effects have been noted where as 
many as three applications a year were made. Die-back and fruit 
ammoniation symptoms have practically disappeared from this grove 
6 WINSTON, J. R., and BOWMAN, J. J. COMMERCIAL CONTROL OF CITRUS MELANOSE, 
U. S. Dept. Agr. Cire. 259, 8 p. 1923. 
7 YOTHERS, W. W. SPRAYING FOR THE CONTROL OF INSECTS AND MITES ATTACKING CITRUS 
TREHS IN FLORIDA. U.S. Dept. Agr. Farmers’ Bul. 933, 38 p., illus. 
