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I'ut contaiu plant food. You will find something very 

 .similar stated by Thomas, who published a book on fruit 

 growing in 1867. These older observations are quite perti- 

 nent when taken together with the fairly recent publications 

 of some of our stations showing that apple trees growing on 

 clay loams or silt loams often fail to respond to applications 

 of fertilizer, and more than that, there are men as you 

 know, who have been eminently successful in growing ap- 

 ples under the so-called sod mulch method. 



In growing apples by means of the sod mulch method, 

 a double crop, in a way, is being produced on the land; a 

 certain amount of plant food must be placed at the disposal 

 ot the trees themselves; a certain amount of plant food must 

 be placed at the disposal of the grass growing between the 

 trees. The experience of IMr. Hitchings is cited as one of 

 the striking proofs that not only may plant food be unneces- 

 sary to some extent, but that there is enough plant food 

 for the trees themselves as well as for grass which may be 

 growing in the orchard. I wanted to make this statement 

 to be sure that there is no misunderstanding on the subject, 

 and to show you later that the observations of apple growers 

 of 100 years ago are sound and that in spite of the excep- 

 tions, the day comes sooner or later in every apple orchard 

 when the addition of plant food from one source or another 

 IS worth while. 



Possibly if apples or pears or peaches ar^ an annual 

 crop, we should realize the plant food relations a great deal 

 more definitely than we realize them today because of the 

 long period through which the trees are enabled to accumu- 

 late plant food, the long growing season of the tree, but it 

 IS true nevertheless that taking the analyses of fruit and 

 the leaves and the twigs and trunks of the trees, that there 

 is being removed in an apple orchard, through an average 

 of ten years. 50 or 60 pounds of nitrogen, about 15 pounds 

 of pliosphoric aeid and 50 to 70 pounds of potash, and when 

 you compare the plant food draught caused bj' fruit trees 

 with that caused by annual crops like corn, you will admit 



