86 
AMERICAN POMOLOGICAL SOCIETY. 
of soda. Tlie organic forms, such as tankage and cotton seed meal are ex- 
cellent. 
As has been already said, phosphoric acid and potash are essential to the 
production of fruit. They are more important than nitrogen; if we can 
say that ' one element is more necessary than another. Both of them are 
naturally found in all arable soils in large quantities and in various chemical 
combinations. They are indestructible by fire, and are the principal ele- 
ments of fertility in wood ashes. Without discussing at length the peculiar 
function which each performs in the economy of plant growth it may suffice 
to say that they are the backbone of all manures for fruits, whether home- 
made or bought in fertilizer sacks. They give vigor and stability to the 
tree and rich colors and luscious quality to the fruit. While nitrogenous 
manures prolong the season of growth and retard the ripening of the fruit, 
they hasten its development and maturity. 
The cheapest form in which to buy phosphoric acid is in bone meal, bone 
black, dissolved bone or as dissolved phosphate rock. The latter is noth- 
ing more than the fossil means of prehistoric animals, mixed with various 
mineral compounds, thus making vast beds of rock boulders or pebbles. Pot- 
ash is most cheaply bought as muriate of potash. Sulphate of potash is 
also an excellent form in which to buy it in the market. 
It has been formerly' stated that there are large quantities of both potash 
and phosphoric acid in the earth. Fortunately they are very largely in such 
forms as to be unvailable to the immediate growth of vegetation. Tillage 
is the key that will unlock the combinations. The process may be slow, 
and it is well that it is so, but it is sure. We may sometimes wonder why 
stirring the soil frequently causes our crops of various kinds to grow so lux- 
uriently. There are several reasons, one of the chief of which is, that it 
keeps the soil loose and porous, so the moisture and air may penetrate it, 
and in their - own rnysterious way dissolve the potash and phosphoric acid 
that has lain there unappropriated by the vegetable world through un- 
known ages. And that is one reason why humus, which is nothing more 
than decaying vegetation,- helps to make things grow. It makes it spongy 
and able to hold more moisture than a hard and compact soil. 
Surface tillage also has a wonderful effect in keeping the moisture in the 
subsoil from escaping. It not only keeps down weeds, but it forms a dust 
mulch which acts like nature’s covering of the soil in the deep forests. It 
need not be deep, and indeed it should not be so, especially in an orchard 
or other fruit plantation, else the roots will be disturbed more than is for 
their greatest benefit, and that of the parts above ground. 
There have been repeated experiments, by the several Experiment Sta- 
tions, and, in some cases covering a long series of years, for the purpose 
of determining wdiat tillage would do in this direction. Neither have private 
experimenters been idle. It may, perhaps, be sufficient to mention only one 
of the latter class, because it- is a most notable case of the good effects of 
thorough tillage, and because it may be duplicated ten thousand times by 
as many or more fruit growers in practical every day life. It is that of 
Mr. Willis T. Mann, in the treatment of an old and unprofitable apple or- 
chard in Western New York. 
In the first place, he felt that the trees were too thick. That they were 
starving for space under ground, if not above. Therefore, he cut out half 
the rows each way, leaving but one-fourth the original number of trees. 
He then plowed it thoroughly, and we might think too deeply, for the plowed 
