APPLE GROWING 



more — and when the leaves are of good size 

 and a dark green In color, there Is little need 

 of nitrogen. But when trees are not growing 

 satisfactorily and the leaves have a sickly yellow 

 color, then the need of nitrogen Is evident. On 

 early soils and In long growing seasons nitrogen 

 may be more freely and safely used than under 

 other conditions. 



The effect of phosphoric acid and potash on 

 the tree and fruit Is much more uncertain. They 

 are supposed to Influence the quality and the 

 flavor of the fruit, giving better color and 

 flavor, and this they undoubtedly do to some 

 extent. Potash probably gives the leaves a 

 darker green color. The precise effect of these 

 two elements Is at prsent a subject of much 

 discussion, one set of Investigators maintaining 

 after a long and careful Investigation that these 

 effects are too small to be worth while, and the 

 other claiming that they have a marked effect 

 In the ways above Indicated. The only safe 

 guide is the actual local result. If the fruit Is 

 satisfactory In every way It will be of little use 

 to try fertilizers. On the other hand, If It is 

 not, then It will pay to experiment with them. 

 The needs of and the results on different soils 

 are so variable that it Is always wise to experl- 

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