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the disease is the usually dark green colour of the foliage, rank 

 growth and large thick skinned fruit These symptoms are 

 soon followed by the staining and dying back of a few twigs, 

 and by brown stains formed on some of the fruits. The fruits 

 developed are very prone to split and drop prematurely. In 

 the first stage of the disease either the stained fruit or the 

 stained dying twigs must be present to determine with 

 certainty the presence of the malady. Trees affected with the 

 disease may grow for years and shew only one of these 

 characters ; in other cases all the symptoms may be present, 

 but to a very slight extent, so that very careful search must be 

 made to find them. As the disease progresses, the brown 

 staining of the fruit and twigs becomes more abundant and the 

 dying back of the twigs occurs all over the tree ; eruptions 

 form on the young and old twigs ; nodal swellings, due to the 

 gum pockets, become very abundant ; and the tree assumes the 

 dense foliage and regular outline described above. In this 

 stage of the disease many fruits set, but they usually turn 

 yellow, become stained, split and fall before maturity, only a 

 few, if any, reaching full size. Soon the gum eruptions extend 

 to the old limbs and these die back. The rank new growth 

 becomes limited to the centre of the tree ; here branches grow 

 luxuriantly for a time, only to become stained and die back 

 later. The tiee then assumes the ragged appearance described 

 above. In this stage no fruits set, and indeed, the tree has 

 become so sick that no flowers are formed. This disease is not 

 accompanied by profuse blooming, as is the case in blight ; on 

 the contrary, the tendency is to produce very little bloom. If 

 the disease is allowed to continue unchecked the trees will 

 ultimately cease to grow and finally die. 



Cause. — The cause of the die-back is not yet thoroughly 

 understood. For several years experiments have been under 

 way to determine whether various fertilisers may not produce 

 the malady. Experiments have also been conducted in the 

 laboratory with water cultures. In these experiments various 

 forms of pure chemical manures were employed, the amounts 

 used being under absolute control. From the results of these 

 experiments and from extensive field observations in many 

 parts of the State, it seems highly probable that the disease is 

 caused by malnutrition. In most cases it is probably induced 

 by excessive use of organic nitrogenous fertilisers. As before 

 stated, trees near stables, chicken houses, privies/ &c, are very 

 commonly affected by the disease. Heavy applications of 

 cotton seed meal, dried blood, or other highly nitrogenous 

 organic fertilisers are frequently followed by the appearance of 

 the trouble. Groves fertilised continuously with organic 

 fertilisers rich in nitrogen are usually more or less affected 



