Gloucester County Democrat. (Woodbury, N.J.) 1878-1932, 1899-05-04

SOIL FERTILITY.
Grain Farming Exhausts--The Dairy
Gives Constant Gnin.

Grain Farming ENhausts-The Dairy
Gives Constant Gnin.
The amount CT principal elements OF
fertility removed from the soil in prod
nets sold from the farm and the amount
returned to it N the form Of manure
depend largely upon the system Of farm
ing practiccd. 1t is well known that
soils under continuous cultivation de-
cline in fertility much More rapidly
than those kept in grass This IS due
not only to the constant removal of fer
tility in the crops harvested and sold
from the farm, but also to the fact that
under most systems of continuous cul-
ture the soil is left bare large part of
the time and thus subjected TO loss
from teaching, washing and oxidation.
On the other hand soils in grass are
protected almost entirely from the lat
ter losses The roots of the plants bring
up the fertilizing constituents from the
lower layers of the soil. and they aceu-
mulate at the surface of the soil in the
decaying remains of the vegetation.
Thus in case of grass lands, while there
is no actual gain in total amount Of
fertilizing constituents in the soil, the
plant food is made more available and
accessible. These facts, according to
farmers bulletin No. 81, explain the
apparent recuperation of soils which
have been exhausted by continuous cul-
ture when kept under grass for num-
Der of years. If leguminous plants are
subtituted for grasses, there may be an
actual gain in fertility due to the nitro
gen which these plants are capable of
collecting from the air.
When the lands are gTazed by sheep
and cattle. the soil fertility is drawn
upon to the extent Of the nitrogen,
phosphoric acid and potash required to
build the blood. bone and tissue of the
animal body This is considerable in
the case of growing animals but in
significant in the case of animals which
have made their growth Especially of
bone) and are simply maintained or
fattened on the pasture. If, however,
concentrated feeds are used in addition
to pasture and the manure produced is
returned to the land. there is an actual
gain in fertility of the land. 1t will
thus be seen that exclusive grain farm
ing or continuous culture of Il single
crop has much greater tendency to
impoverish the soil than stock raising
or combined grain and stock raising A
comparison of the amount CT plant food
removed from the soil and the amount
capable of being returned to it under
different systems of husbandry has been
made by the Minnesota experiment
station The systems taken into consid-
GRAFTON were all grain farming, mixed
grain and general farming, mixed po
tato and general farming, stock farm
ing and dairy farming, examples being
selected which represented the different
systems. In each case the farm is con
sidered to contain 100 acres.
In the example of all grain farming
selected no stock was kept and no fer
tilizers Of any kind were applied TO the
land, the small amount of fertiizing ma
terial which necessarily accumulated
was disregarded. and the grain was all
sold from the farm, Tho entire farm
of 1850 acres was under cultivation.
The crops raised were 100 acres of
wheat, 40 acres of barley and 30 acres
of oats yielding 5. 40 and so bushels
per acre respectively. 1t is calculated
that the fertility removed from such a
farm in the grain and straw of one
years crops amounted to 2, 400 pounds
of phosphoric acid, 4.020 pounds of
potash and 5000 pounds CT nitrogen.
This does not include the fertility re-
moved by the weeds which often is
very large-and the amount of nitrogen
lost from the soil through teaching and
the decomposition of humus-
The amo-nt of nitrogen thus lost
from rich prairie soil recently brought
under this system Of farming is three or
four times that removed from the crop.
1t was found from experiments conduct
ed at this station that when prairie
soil is first brought under cultivation
the humus oxidizes rapidly, but as the
soil grows older the humus content di-
minishes and the oxidation of the hui
mus goes on more slowly.
Without attempting to give fully the
results of the other systems Of farming,
as presented in the bulletin, it may be
said in brief that in system of mixed
grain and general farming which was
studied there was an annual loss of
about l, 600 pounds each of phosphoric
acid, potash and nitrogen. There was,
therefore, loss CT about two-hfths as
much phosphoric acid, one-fourth as
much potash and one-sixth as much nj
trogen as in all grain farming.
In system of mixed potato and gem
eral farming the approximate loss
amounted to 991 pounds of phosphoric
acid, 2, 435 pounds of potash and 2, 1853
pounds of nitrogen. Deducting the nj
tr9gen accumulated in the soil through
a clover crop the net loss of nitrogen is
less than !, 900 pounds.
In the example of stock farming Sc
lected for study there was approx
mately a gain Of 80 pounds of phos-
phoric acid and loss of 80 pounds of
potash and S98 pounds of nitrogen.
The loss of nitrogen was more than bal
anced by the gain due to the clover
crop, SO that. on the whole, there was
practically no loss of fertility from the
farm.
In the example of dairy farming the
figures show gain of rs pounds of
phosphoric acid and loss of So pounds
of potash and So. o pounds of nitrogen.
The loss of nitrogen. however, is again
offset by the gain through the clover
crop, so that there is practically no loss
of fertility in dairy farming. under
proper management. but rather con-
slant gain.
These studies are certainly highly in
structive, and their details as given in
ths bulletin are fall Of interest.