Democratic Northwest. [volume] (Napoleon, Ohio) 1869-1894, 1892-03-17
LECTURE DELIVERED
BY l.. N. BONHAM,
ESQ.
Before the Students In Agriculture at
the Ohio state University on
the Rotation of Crops.

| roIIoWinB IS an ABSTRACT or q lecture
delivered by L. n. Bonham, secretary
Of the Ohio State Board of Agriculture,
before the agricultural department OF
the Ohio State University:
After brief introduction showing
the history Of rotation and fallows in
Europe, and that in China fslIows are
not known, the speaker noted some
OF the difficulties in arranging or
prescribing rotation suited to every
locality. The success OF rotations
depend not only on the climate and
soil on the market and labor at ones
command. There are two chief and
general reasons why rotation of crops is
necessary. l, For the conservation of
the soil. 2, For the sake of economy.
Removal ofcrops takes from the farm
nitrogen, phosphoric acid and potash,
Butter is the only product which does
not deplete the soil. Reckless farming
in time depletes the soil below the
point of profitable production, but the
soil is practically inexhaustible, since
an acre of soil to the depth of one foot
contains nitrogen 5000 pounds, phos-
phoric acid $1,000 pounds, potash l2,-
200 pounds. A twenty-bushel wheat
crop takes of nitrogen 80 pounds,
phosphoric acid 15,1 pounds, potash
1876 pounds. If we take off both straw
and grain 1t will take 266 years to re-
move the nitrogen; 1,003 years to re-
move all the phosphoric acid, and 500
years to remove all potash.
Commercial fertilizers are poor de-
pendence for keeping up fertility.
They can only feed the crops in part
and are too costly to be used in storing
up fertility for future crops,
Fertility is constantly being unlocked
by chemical action, by frost and
moisture.
Nitrification is the most important
chemical operation in nature, without
which we cannot conceive of contin-
ued fertility. The condition favoring
nitrihcation are: l, porous soil 2,
warmth, as nitrification is dormant at
forty-two degrees and most active
when warm enough to decay meat and
vegetables; 3, moisture in regular and
moderate supply.
Clover and grasses shade the soil,
retain moisture, render it porous and
favor nitrification while filling in veg
etable matter.
Nature rotates crops. When the for
ests of oak and hickory have been re-
moved thick growth of evergreen
appears. In New England, where
white pine forests have been removed,
the maple, chesnut and oak have
sprung up. A similar rotation is found
in timothy meadows, followed by
blue glass.
Besides general, there is a special
depletion by each variety of crop. AS
each crop seems to have special wants,
we increase crops by change, but
chemistry has not been able to tell US
why. A change of variety of feed is
needed for animals, but so long as the
rations balanced, chemistry can not
tell us why the changes are beneficial.
Plants vary in power to appropriate
food. Glover, We say has high power
to gather nitrogen, while wheat has a
low power; hence clover precedes
wheat well. Wheat grows mostly in
cool weather when nitrification is slow
or dormant; hence the soil for wheat
must be rich nitrogen. On the other
hand corn grows wholly in the warm
weather; hence needs less nitrogen to
make crop.
We may say plants have favorites in
plant food. Wheat, for example, takes
one and quarter pounds of potash to
every three and quarter of phos-
phoric acid. Potatoes take three aud
a quarter of potash to one of phos-
phoric acid.
Leaves of plants take on from the
atmosphere, one-half the weight of the
plant. This power varies, and broad
leaf should follow narrow leaf in rota-
ton.
Plants take food only in soluble or
gaseous form. 1t is a wise arrangement
that soil does not dissolve as freely as
sugar or salt or one soaking rain would
ruin us. Stirring the soil favors disin-
tegration, hence plowed or hoed crops
should follow grasses.
Grasses are conservers of soil and
and prevent washing and bleaching.
Rotation checks some kind of insect
ravages and fungi. The corn root
worm does not feed on clover roots.
The clover root borer does not bore
corn roo or wheat, oats, and etc.
Growing variety of crops is inteili-
gent or scientific rotation is good econ
omy. 1t divides the labor of the year,
reduces amount oftpams, gives regular
employment the Year around, and has
moral advantages of great significance.
Growing one crop only dwarfs men
as well as impoverishes soil.