144 The Principles of Fruit-growing 



bearing trees. Where potash is not known to be lacking, 

 the smaller amount may be used, or after a little testing 

 it may even be omitted entirely. With the smaller amount 

 of potash, the essentials of the present combination are 

 carried in 500 pounds of a 6-10-5 fertilizer or its equivalent. 

 In the usual ready-mixed fertilizers, the nitrogen is likely 

 to be carried in ammonium sulphate, with which some lim- 

 ing may be necessary if many applications are made, and 

 especially if leguminous cover-crops or permanent covers 

 are desired. In special or in home-made mixtures, the 

 various elements may be carried in any of the materials 

 indicated." 



Other suggestions for apples and pears. "When the 

 stage is passed hi which extended cropping between the 

 trees is possible, and the burden of fruit becomes great/' 

 Wheeler advises, "special care should be taken to apply 

 an abundance of potash and phosphoric acid annually, and 

 only enough nitrogen from legumes or fertilizers to insure 

 adequate foliage, satisfactory wood-growth, and abundant 

 fruit-spurs. For this purpose a suitably compounded 

 complete fertilizer may be employed. If legumes are 

 found to supply enough nitrogen one may employ annually 

 from 200 to 600 pounds an acre of acid phosphate or basic 

 slag meal, and from 50 to 400 pounds an acre of the muri- 

 ate or high-grade sulfate of potash. If the double manure 

 salt is used as the source of potash instead of the muriate 

 or the high-grade sulfate of potash, the total application 

 should amount to approximately twice as much an acre, 

 because of the lower potash-content of the latter. 



"The nitrogen for the orchard may be supplied in one, 

 or on light, open soils, in two applications of nitrate of soda 

 at such a rate that the total application for a season will 

 not exceed from 100 to 300 pounds an acre, dependent 



