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rotting of the tubers. In regions where late blight is known to occur, 

 care should be taken to begin the application of the Bordeaux mixture 

 before the attacks of the fungus. In all this work it must be con- 

 stantly kept in mind that the main object is prevention rather than 

 cure. Benefit will undoubtedly result if only clean, healthy potatoes 

 are used as seed. Decayed and discoloured tubers should be fed to the 

 hogs, as it is poor policy to plant them. 



Brown Rot. 

 (Bacillus solanacearum Smith). 



This disease occurs in many parts of the South, and, in addition to at- 

 tacking the potato, is found to seriously injure eggplants and tomatoes. 

 In the case of the potato, the leaves, stems, and tubers are affected. 

 The diseases usually manifests itself by a sudden wilting of the foliage 

 and soon the whole plant may become affected, the leaves and sterna 

 shrivelling and then turning brown or black. The disease reaches the 

 tubers through the stems, producing a brown or black discolouration of 

 the tissues and ultimately a complete breaking down or rotting of all 

 the parts. Brown rot is caused by a bacillus, a minute organism, 

 which multiplies in the tissues and through its action produces they 

 effects mentioned. Various insects, such as Colorado beetles, flea 

 beetles, and blister beetles, serve as carriers of the disease. These in- 

 sects may feed on a diseased plant, and in their visits to adjoining- 

 healthy ones infect the tissues through bites and possibly in other 

 ways. 



TREATMENT. 



Throughout the South, namely, in South Carolina, Mississippi, Ala- 

 bama, and adjacent States where this disease is known to occur, a 

 thorough system of spraying, such as recommended for early blight, 

 should be followed. In addition, all diseased vines should be removed 

 and destroyed as soon as possible, and the tubers should be dug and 

 either used at once or stored in a cool, dry place. In planting it would 

 be well to avoid land which has just been used for tomatoes or egg- 

 plants, and finally seed tubers from localities where the disease is 

 absent should be used if practicable. 



Potato Scab. 



(Oospora scabies Thaxter.) 



Scab is one of the most widespread diseases affecting the potato. In- 

 juries of various kinds may produce a roughened surface, but it is safe 

 to say that most of what is known as scab is due to the attacks of a 

 minute parasitic fungus, first studied and described by Dr. Roland 

 Thaxter, of Harvard University. 



treatment. 



Potato scab may be successfully controlled by treating the seed pre- 

 vious to planting. Two fungicides are used for the purpose, namely, 

 corrosive sublimate solution and formalin solution. To prepare the 

 first, dissolve ounces of corrosive sublimate, or bichloride of mer- 

 cury, in about 2 gallons of hot water and after ten or twelve hours 

 dilute with clear water so that the whole quantity makes 15 gallons. 

 Corrosive sublimate is a poison and must therefore not be placed where 



