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tliem on a particular soil. In the fertilisation of the orange, 

 however, the matter is not so easily determined ; only the 

 observations of a series of years will give results which can be 

 depended upon. An orange grower may fertilise with one 

 element one year and get good results, but this is no evidence 

 that the same element used the next year, or year after year, 

 will prove beneficial ; it may, indeed, in prolonged treatment, 

 lead to deterioration and disease. It is this difficulty in ex- 

 perimenting and drawing correct conclusions that acconnts for 

 the present poor understanding of rational methods of manur- 

 ing the orange. 



The orange appears to be ver}^ sensitive to methods of treat- 

 ment and fertilisation, and several of the most serious diseases 

 are either caused or aggravated by errors in these. The 

 present paper is based largely on the experience of intelligent 

 orange growers and upon such observations as the writer has 

 been able to make in the course of investigations of oiange 

 diseases. 



Fertilising fok G-rowth and Fruit. 



Primarily the orange grower desires to know how to fertilise so 

 as to stimulate either growth or fruit production. With oranges 

 as with many other agricultural plants, one may fertilise 

 in such a manner that excessive growth is stimulated at the 

 expense of fruit production. A strong nitrogenous fertiliser 

 results usually in much growth and little fruit. This seems to 

 be particularly true if ammonia is added in an organic form. 

 While trees are young it is probably well to favour the growth 

 of wood principally, but at the age of seven or eight years from 

 the bud, the tree, if it has grown properly, Avill have attained 

 sufficient size to begin to produce a fair quantity of fruit. It 

 should then be given a slightly modified fertiliser, containing 

 more potash and phosphoric acid, and less nitrogen, to stimulate 

 fruit production as much as possible. The so-called chemical 

 manures appear to be much moi-e active in stimulating fruit 

 production than organic manures. 



Effect on Quality of Fruit. 



The experience of many orange growers indicates that the 

 quality of the fruit may be largely controlled by fertilisation. 

 As oranges are purchased very lai-gely on their appearance and 

 quality, this becomes an important consideration in manuring. 

 Many intelligent growers are coming to believe that the best 

 results can be obtained by giving the trees an application of 

 that element only which seems to be lacking, and not using, as 



