316 



ENCYCLOPEDIA OF PRACTICAL HORTICULTURE 



Note. — In the above calculations the 

 following data are used: Forty trees per 

 acre in an orchard 25 years old yield, on 

 an average, one hundred and sixty (160) 

 barrels. One barrel contains two bushels 

 and three pecks. 



We have here the number of pounds of 

 nitrogen, phosphoric acid and potash es- 

 timated as contained in one barrel of the 

 fruit, and the amounts removed per acre 

 by a good crop. None of the quantities 

 are at all excessive, and the cost of re- 

 turning them would not be great. The 

 largest demand is on the potash in the 

 soil; next comes the nitrogen, and lastly 

 the phosphoric acid. In the case of the 

 leaves, the nitrogen stood first. 



For the vigorous development of the 

 tree and an abundant crop of fruit, the 

 soil must contain these constituents in a 

 more or less immediately available con- 

 dition. It is for this reason, as well as 

 to replace the exhausted plant food, that 

 fertilizers are necessary to profitable 

 apple growing. 



Tiitrogen 



To supply nitrogen, some organic ma- 

 nure is perhaps the most economical. 

 Barnyard manure or the turning under 

 a leguminous crop (the latter being rich 

 in nitrogen) are to be recommended. Be- 

 sides adding nitrogen, they furnish hu- 

 mus or decaying vegetable matter, which 

 serves a useful function by liberating 

 carbonic acid, and which in turn sets 

 free locked-up forms of mineral food. 

 Humus, moreover, has much to do in 

 bringing about good tilth and in the re- 

 tention of soil moisture. As the period of 

 growth and fruit development In the ap- 

 ple is comparatively long, organic ma- 

 nures in most instances will probably 

 give better returns than those containing 

 more soluble forms of nitrogen, such as 

 nitrate of soda or sulphate of ammonia. 



Potash and Pliospliorio .Void 



To furnish potash and phosphoric acid, 

 we would first mention wood ashes. In 

 many parts of the country they are the 

 cheapest form in which to purchase these 

 constituents. Moreover, they possess them 

 in the relative proportion best suited to 



tree requirements and in a condition 

 that renders them easily available. 



If wood ashes are not obtainable, kainit 

 and muriate of potash may be substituted 

 to supply potash; and bone meal and sup- 

 erphosphate, the phosphoric acid. Bone 

 meal contains two per cent to three per 

 cent of nitrogen, in addition to the phos- 

 phoric acid, but requires a greater length 

 of time in the ground to give up its con- 

 stituents: its effects naturally last longer. 

 For this very reason it is often advocated 

 for orchard fertilization. 



Both wood ashes and bone meal furnish 

 lime, which we have seen to be a neces- 

 sary and somewhat important element. 



Soils differ so much in composition 

 that it is impossible to state definitely 

 the amounts of these fertilizers that 

 should be employed in all cases. The 

 wants of the tree for fruit and leaves 

 have been given and the principles for an 

 economical return of these requirements 

 indicated. In conclusion, it may be said 

 that the best and most profitable crops 

 can be obtained only when the soil con- 

 tains what might be thought to be a large 

 amount of plant food, the greater part of 

 which is more or less assimilable. A 

 .good tilth, among other advantages, tends 

 to a good root development. In such the 

 rootlets are able to procure food from a 

 much larger area than otherwise; but in 

 every orchard, owing to the disposition of 

 the roots, there must of necessity be 

 much unoccupied soil, and hence the im- 

 portance of supplying liberally and in ex- 

 cess of that which is absolutely needed 

 for a season's growth and fruit, those 

 forms of plant food which we have been 

 considering. 



About 200 pounds of ground bone and 

 200 pounds of muriate of potash, applied 

 annually to bearing orchards should fur- 

 nish an abundant supply of phosphoric 

 acid and potash. 



Leaves in proportion to their weight 

 contain a much larger amount of plant 

 food than the fruit. The amount con- 

 tained in 1,000 pounds of leaves gathered 

 in September was 8.87 pounds of nitro- 

 gen. 1.94 pounds of phosphoric acid, 3.92 

 pounds of potash, this being the average 

 of five varieties analysed. 



