FERTILIZERS IN FRUIT GROWING 117 



on either other fertilizer ingredient. Thus the ashes of de- 

 ciduous trees contain three times as much lime as potash ; 

 those of conifers nearly six times as much. The dispropor- 

 tion between potash and lime is even greater in the case 

 of leaves. On the other hand, most fruits contain more 

 potash than lime. But the total annual growth of the tree, 

 fruit included, takes, I believe, much more of lime in the 

 aggregate than of potash. 



Another reason for numbering lime with the fertilizers 

 to be applied to orchards is this : If any ingredient of the 

 soil is lost by leaching, it is sure. to be lime, and more of 

 lime is likely to be lost in this way than of potash or any 

 other mineral matter. We are told often enough that soils 

 absorb or fix plant-food, potash, ammonia and phosphoric 

 acid, and hold them so that they will not, readily at least, 

 leach out. We are not told, perhaps, often enough, that 

 any fixing of these things is only possible by an unfixing, 

 a releasing, of some other base — usually lime; so that, if 

 the soil is leached by rains at any time of the year, putting 

 on potash salts, to a certain extent, exhausts lime. Gener- 

 ally, perhaps, this loss is not a serious one, but on soils 

 naturally poor in lime it may be serious, and trees may 

 suffer for want of lime, while they have abundance of the 

 more expensive ingredients — potash and phosphoric acid. 

 Nitrogen, phosphoric acid, potash and lime, then, are the 

 things which fruit growers must regard in fertilizing or- 

 chards. The other necessary elements of plant-food will 

 be supplied incidentall}' in supplying these. 



Some plants are naturally deep-rooted, some shallow, 

 some have a strong tap-root, others throw out several strong 

 roots from the same point without a tap-root. But while 

 all this is true, it is likewise true that, in most cases, a tree 

 or shrub cannot closely follow the architectural plan pecu- 

 liar to it, but is forced by outside conditions to modify this 

 plan. If the tap-root strikes a ledge, it must turn aside, 

 and being in this way made less effective, the lateral roots 

 grow the more to take its place. If roots strike a stiff clay, 

 and find too little air, they slacken or stop their growth 

 there, and grow the faster elsewhere. Hence, it is true, I 

 think, of our orchards, that the shape and extent of the 



