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disease until they are nearly full grown the danger of infection 

 is past. This is the case also with the fruits, and therefore 

 spraying to prevent the disease must be done early while the 

 fruits are small. After they reach an inch in diameter they 

 appear to be safe from infection and spraying may then be 

 discontinued. 



Preventive Measures. — In the summer of 1894 experiments 

 with various fungicides were carried on at Stanton and Citra, 

 with a view to find a preventive of the disease. The copper 

 fungicides, i.e., Bordeaux mixture and ammoniacal solution of 

 copper carbonate, were found to almost wholly prevent the 

 disease if properly applied. In two plats of lemon trees at 

 Stanton, sprayed with Bordeaux mixtures 6 pounds of copper 

 sulphate and three and a half pounds of lime to 50 gallons of 

 water), melanose was absolutely prevented, the most careful 

 search failing to disclose a single fruit showing the characteris- 

 tic spots. The sprayings were made once a week and twice a 

 week respectively, for a term of ten weeks, beginning February 

 3rd. On an orange tree sprayed at the same time with the 

 lemons the treatment was equally effective. However both the 

 lemon trees and orange trees were somewhat injured by the 

 Bordeaux mixture, probably largely because of the numerous 

 sprayings given. On adjoining unsprayed lemon trees from 2 

 to 4 per cent, of the fruits and a larger per cent, of the foliage 

 were considerably spotted with the disease. Perhaps half the 

 spotted fruits were so badly disfigured as to be unsaleable. 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 Oitra, several plants of 

 very badly infected orange trees were sprayed with Bordeaux 

 mixture (6 lbs. of copper sulphate and 3 1/2 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 plats 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 abandance of scale insects on sprayed trees. As melanose 

 was absolutely prevented by Bordeaux mixture of the strength 





