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the diseased areas, a method coiuaionly recommended for this sort 

 of disease as a means of preventing the spread of the fungus to un- 

 infected areas, and the treatment of the soil with substances having 

 some degree of fungicidal action. The ditching seemed especially 

 advisable, because the fungus is superficial, never penetrating the 

 soil for more than a few inches. The substances added to the soil 

 included lime, sulphur, chloronaphtholeum, and copper sulphate. 

 These were selected as being fairly easily procured and quite cheap, 

 if not too great quantities should be necessary for their effective 

 use. Other substances used included potassium permanganate and 

 potassium bisulphite. The effect of breaking up the soil by means of 

 heavy hoes, a method quite common in cultivating coffee, was also 

 tried in some of the check plats and in all of the other plats. Pre- 

 viously to this cultivation all diseased trees and stumps and the 

 partly decayed vegetable debris common in such places were re- 

 moved. For the lime experiment the soil was first broken, after 

 which the lime was applied at the rate of 500 grams per square 

 meter, being thrown into shallow trenches and immediately covered. 

 The trenches being close together and parallel, the application was 

 thorough, no part of the surface being overlooked. The ground was 

 sprinkled with water to slake the lime and then worked with hoes 

 to mix it with the soil. Whenever a diseased tree had been re- 

 moved an extra amount of lime was added. Similar methods were 

 used in applying the sulphur, care being taken to mix it thoroughly 

 with the soil. Two areas were treated, one receiving 500 grams per 

 square meter, the other about one-fourth of this amount. The chlo- 

 ronaphtholeum, a petroleum distillate product of the same class as 

 carbolineum, was used in one of the worst diseased places. It was 

 applied at the rate of about 50 cubic centimeters per square meter, 

 being poured in 5 per cent solution into small holes which were 

 made about a foot apart. Later the ground was sprayed with this 

 solution and then worked over with hoes to secure more thorough 

 penetration. 



During the three years since the experiment was begun no trees 

 have died in plats receiving lime and the heavier application of 

 sulphur. In the check plat adjacent to that receiving lime 6 per 

 cent of the trees have died, and about 3 per cent of the trees in the 

 plat with the smaller application of sulphur and in that receiving 

 the chloronaphtholeum. In a plat of anamii showing this disease 

 an application of chloronaphtholeum amounting to 100 cubic centi- 

 meters of the undiluted preparation and another with the excessive 

 amount of 450 cubic centimeters per square meter were made. The 

 heavier application stopped the disease without injuring the healthy 

 plants. The disease was unchecked by the lighter application, all 

 the plants in this plat being killed by the fungus. In any event 



