The Portland daily press., 1878-05-08
AGRICULTURAL.
THE HOUSEHOLD.
Some oGlhe Effects of TiIlage.

At the last December meeting of the Con.
necticut State Board of Agriculture, pa
per was read by Prof S. w. johnson of New
Haven, on the reasons for tillage as based on
the relations of water to soils and to crops.
We quote below his concluding paragraphs:
The practical differences from these facts are
obvious. That stratum of the soil which is
subjected to loosening tillage is always dried
thereby. A wet soil may sometimes be ad-
vantageously plowed for the purpose of dry
ing it. A dry soil may be made too dry by
deep and repeated tillage. The reasons are
1. By loosening the soil is made to expose a
vastly greater evaporating surface to the at
mosphere than the compact soi.presents. 2.
The capillary connection of the loosened earth
with the underlying soil is impaired, and it's
power of taking up and distributing bottom
water is diminished. 3, The rain that falls
upon it flows more freely and completely into
the subsoil. Thus its rate of losing water is
increased, and the sources of supply are rem
dered less rapidly effective. 1t is evident that
the amount (depth and frequency of tillage
which would benefit crops on a clay soil,might
damage those on sandy one.
To conserve the water of loose.textured
soil, its main tillage should be shallow, so that
the bulk of the earth remains compact enough
to hold the rain and to transmit bottom water
steadily from the subsoil upwards to the roots
of crops. The surface only, which has been
puddled by the latter and earlier rains, need be
disturbed in spring-time to prepare aseed-bed
and to cover in manure. That surface, as Oft
en- as it settles to compactness or forms a
crust, should be loosened up again with the
horseshoe, so as to maintain over the water
conducting body OF compact earth a relatively
non-conducting layer OF loose soil, to cut off
the escape of moisture into the atmosphere.
Summer tllage, to conserve moisture,
should be shallow, and should not extend to
the roots, unless, indeed, with the object of
compelling them to develop lower down and
nearer to the water supply. Generally, how
ever, the depth of the well-manured stratum
is but small, and as little as possible of it
should be withdrawn, by frequent stirringland
consequent drying, from serving as forage
ground for the roots of crops.
1t is however, easy to see that the effects of
surface tillage will differ according to the ma
ture of the soil. If, instead of sand or soil
made up of solid, coarse particles, it is a loan
which spring preparation has reduced, not to
dust, but to Jumps like sand-grains in size,
but themselves porous and easily broken to
dust or made finer by the passage OF the cul-
tivator, then the loosening effect oil tilIage on
the mass may be more or less compensated by
its pulverizing effect ON the Jumps.
Again, unless there be uninterrupted capil-
larry communication between bottom-water
and the surface-soil, surface working will not
prevent the inevitable drying out of the filth /;
nay, it may in the latter stages of that drying
out hasten the result.
A light, loamy land, underlaid at a little
depth by coarse sand. and deeper still by a
loose gravel, will subject the vegetation on it
to severe extemes of water supply, for when
heavy rains fall, the fine interstces ofthe sur
face will remain gorged, because the coarse
material below cannot suck the water down,
and when, in drouth, the surface-water is ex-
hausted, there is no capillary attraction be.
tween the loan and bottom-water. Subsoils
are not, however, necessarily deficient in cap
illarity because they contain some gravel. A
proper kind and amount of porosty insures
the ready distribution of water, whatever be
the name of the material.
The use of the roller after narrowing in
seed, and of striking with the fiat of the hoe
upon the hill after planting, is obviously to
facilitate the access of moisture to the seed.
The capillary connection between the sur
face soil and the moist earth below is largely
interrupted by putting in the seed, for that is,
in itself, a loosening process. The soil must
be compacted in order to restore that connec-
ton and insure to the seed and young plant
steady and sufficient supply of water.