316 
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. 
Nitrogen 
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 Phosphorie Acid 
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 
ENCYCLOPEDIA OF PRACTICAL HORTICULTURE 
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. 
