37 
spotted with the disease. Perhaps half the spotted fruits were so 
badly disfigured as to be unsalable. In a plat of lemon trees sprayed 
weekly with ammoniacal solution of copper carbonate (5 ounces to 
50 gallons), beginning February 24 and continuing eight consecutive 
weeks, no melanose could be found on any of the sprayed trees. How- 
ever, very little developed on the unsprayed trees adjoining this plat. 
In another series of experiments at Citra, several plats of very 
badly infected orange trees were sprayed with Bordeaux mixture 
(6 pounds of copper sulphate and 34 pounds of lime to 80 gallons of 
water). In one of these plats sprayed twice, April 19 (shortly after 
flowering) and May 16, melanose was almost wholly prevented. Only 
two slightly spotted fruits were found on the entire plat of twenty-five 
large trees. Certainly not one-tenth of 1 per cent of the fruit showed 
even a trace of the disease. On the adjoining unsprayed trees fully 
90 per cent of the fruit was diseased, some 50 per cent of it being 
very badly disfigured. In these experiments the trees also were injured 
to some extent, probably largely because of the abundance of scale 
insects on sprayed trees. As melanose was absolutely prevented by 
Bordeaux mixture of the strength above, it is highly probable that 
weaker sprays would be equally effective. It is likely that more spray- 
ings will be necessary in treating melanose on the lemon than on the 
orange because of the more extended flowering period of the former. 
Although the experiments were mostly with Bordeaux mixture, which 
has proved fully effective in preventing the malady, it is very likely 
that ammoniacal solution of copper carbonate will be the most practical 
remedy, because it is not so apt to injure the trees and will probably 
prove as effective as Bordeaux mixture. 
The following is a Summary of practical directions for keeping mela- 
nose in check: In treating the lemon for melanose, spray with Bor- 
deaux mixture! or ammoniacal solution of copper carbonate.? Spray 
first about a month after the beginning of the spring blooming, or 
1Take 6 pounds of copper sulphate and 3 pounds of good lime to 80 gallons of 
water. Slack the lime carefully and dissolve the copper sulphate; then dilute each 
constituent with water to 25 gallons and mix. Add 6 pounds of soap, dissolved in 
as many gallons of hot water, and finally add enough water to bring the mixture up 
to 80 gallons. A resin soap suitable for adding to fungicides can be prepared very 
easily as follows: Take 40 pounds resin, 20 pounds sal soda (crystalline), and water 
to make 25 gallons. Place the resin and sal soda in a comparatively large kettle 
with 5 quarts of water. Boil, meanwhile stirring briskly, until the resin and sal 
soda are thoroughly melted together and form a frothy mixture without lumps. 
Now add 20 gallons of cold water, pouring it in rather slowly and with short intervals 
between, to avoid chilling the mixture too suddenly. When all of the water is 
added, bring to a boil; then pour out the hot solution, straining through a coarse 
cloth, and add sufficient water to make 25 gallons of the solution. This, if correctly 
made, forms a thick, dark-brown, translucent, sirupy solution, which may be pre- 
served as a stock preparation. About 2 pounds of soap are contained to the gallon, 
and the cost is only about 14 to 24 cents per gallon, while ordinary good hard soap 
costs five to twelve times as much. 
?See directions for making on p. 24. 
