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often light red color. This change of color can also be caused 

 b}' a lack or an excess of moisture, or by insects at the roots, but 

 often, even in those cases, an application of fertilizer will restore the 

 normal color. 



On account of the method of application, it is essential that the 

 fertilizer ingredients should not be caustic or acid, so as to injure 

 the foliage. As all inorganic salts cause more or less injury when 

 applied in the heart of the plant, it becomes necessary to employ 

 some of the ingredients in an organic form. For nitrogen, neither 

 nitrate of soda nor sulphate of ammonia can safely be used in the 

 crown. As a source of nitrogen, cotton-seed meal is very good and 

 dried blood is very desirable also, as well as high-grade tankage. 



For phosphorus it is not safe to use the acid phosphate in large 

 quantities, especially the double acid phosphate, which seems to be 

 more acid than the regular 14 to 15 per cent product. Steamed bone 

 is very good; it causes no injur}^ and the pineapple will be able to 

 take from it as much phosphorus as is needed, provided it is thor- 

 oughly steamed and flocculent. A ground bone in which the particles 

 are granular is not so valuable, because the phosphorus in it is too 

 slowly available. Basic slag can also be used, but although it does not 

 cause as much damage to the foliage as acid phosphate it should be 

 used with caution. 



For potash the sulphate should be used, either the high grade, con- 

 taining 50 per cent potash, or the low grade, containing about 27 per 

 cent potash. Ordinarily these salts cause no injury, but experiments 

 have shown that it is not safe to apply potash alone to small plants, 

 although a pinch may be safely scattered in the leaf bases of large 

 plants. 



METHODS OF APPLYING. 



As previously explained, the root system is very shallow and ex- 

 tends only a few inches away from the stem, therefore the soil in that 

 small space must be rich in plant food in order to produce a large 

 plant and a marketable fruit, In experiments covering over three 

 years it was found that one of the best ways for the plant to take up 

 nourishment is to absorb it from a solution trickling down the stem 

 from the leaf bases. This is fortunate, because in field practice it is 

 difficult to apply fertilizer in any other way than spreading it over 

 the plants. Even where the rows are 3 feet apart the leaves interlace 

 ami ;i great deal of fertilizer drops on the inclining leaves and rolls 

 down and lodges in the leaf axils. The writers recommend scattering 

 the fertilizer so that most of it will lodge directly in the leaf axils. 

 On single rows or on small plants it is best to fertilize each row by 

 itself. On wide beds and where the plants entirely cover the ground, 

 the fertilizer can be spread broadcast and only a limited amount will 

 fall on the soil. 



