138 



and sour orange fruits are not badly deformed wlien attacked by tbe^ 

 fungus after the moist weather of summer sets in. 



Treatment. — During the spring and summer of 1894 extensive experi- 

 ments were carried on by one of tne writers to discover, if possible, 

 means of preventing scab on the lemon. Owing to the irregular bloom- 

 ing of the lemon, the prevention of the disease was found to be a diffi- 

 cult undertaking. However, it was demonstrated that Bordeaux mix- 

 ture and ammonia cal solution of copper carbonate, if properly applied, 

 are efficient. The former is very effective against the fungus, but is 

 more or less injurious to the fruit and foliage of the lemon, while the 

 latter is almost an absolute preventive of the disease and causes very 

 little if any injury to the tree. 



It was found highly important that all infected fruits be removed 

 from the tree and from the ground beneath before blooming begins. 

 This measure is absolutely necessary to insure the success of any treat- 

 ment, and is of itself a great aid in checking the disease. All sour 

 orange trees or sprouts from sour stocks should also be removed from 

 the vicinity of lemon trees, since they are even more ^^ubject to scab 

 than the lemon, and because not only the fruit but also the leaves can 

 support a luxuriant growth of the fungus. 



The disease can be prevented, to some extent, by planting the trees 

 on dry soil and in localities having little rainfall during and immedi- 

 ately after the blooming season. Directions for treating the disease 

 are briefly as follows : 



1. Carefully remove, and burn or bury all diseased lemon fruits, how-^ 

 ever small, either on the trees or on the ground. Cut down and destroy 

 all sour orange trees or sprouts from sour stock in the vicinity of the 

 lemon trees. 



2. Prepare ammonical solution of copper carbonate as follows : Take 

 5 ounces of copper carbonate and stir up with about a pint of water to 

 a thick paste ; then dilute with 1^ gallons of water in a wooden pail. 

 Stir vigorously and at the same time add slowly 2 pints of strong 

 ammonia {}) or 5| pints weaker ammonia wat^^r. (^) Stir until all is 

 dissolvftd, or at least all but a lew granules, and then dilute with water 

 to 60 gallons. 



3. Apply the ammoniacal solution with a pump giving a good pres- 

 sure and furnished with a Yermorel nozzle. The initial spraying should 

 be made when the first young fruits are exposed by the falling of the 

 flowers, the second spraying usually after two are three weeks, a third 

 two or three weeks later on when blooming is nearly or quite over, and 

 a fourth when the fruits are of a size ranging from that of a pea to 

 that of an olive. If necessary a fifth and even a sixth spraying should 

 be made after particularly wet weather. In most cases four and often 

 five sprayings are absolutely necessary. By carefully watching for the 

 appearance of warts on the fruit, particularly during moist weather, 

 the grower can determine when to spray and whether any spraying is 

 necessary after the third application. 



(1) Aqua ammonise fortior (28 per cent.) of druggist. 



(2) Aqua ammoniso (10 per cent.) of druggists. 



