The Use Of Nitrogen
There is no fully satisfactory way of determining
the kind and amount of fertilizer that should be used at any particular
time for any one crop. Perfection in this respect is no easier in
attainment than in other matters. There are, however, means of arriving
at conclusions that are a valuable guide.
In a general way, nitrogen is in scant supply in all worn soils.
Wherever the cropping has been hard, and manure has not gone back to
the land, the growth in stalk and leaves of the plant is deficient. The
color is light. Inability of a soil to produce a strong growth of corn,
a large amount of straw, or a heavy hay crop, is indicative of lack of
nitrogen in nearly every instance.
The legumes, such as clover, and the stable manures are rich in
nitrogen, and when the scheme of farming involves their use on all the
land of the farm, no need of purchased nitrogen may arise in the
production of staple crops. In the black corn soils the nitrogen
content originally was high.
Lands that naturally are not very fertile rarely have enough available
nitrogen. Where timothy is a leading crop, the demand for nitrogen is
heavy. A cold spring or summer, checking nature's processes in the
soil, may cause a temporary deficiency in available nitrogen in land
that usually has a sufficient supply. Associating a rank growth of
stalk and leaf with an abundance of nitrogen, the experienced man can
form a pretty safe opinion regarding the probable profitableness of an
investment in this element. It costs nearly four times as much per
pound as either of the two other constituents of a fertilizer, and so
far as is feasible it should be obtained through the legumes and stable
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