Green-Mountain freeman. [volume] (Montpelier, Vt.) 1844-1884, 1879-01-08
Moisture. Retaining Power of the Soil.

AVWNA VI
have read with much interest the ex-
perimental attempt of the editor OF tie
Rural TO settle the question whether pull
verizing the surface soil checks the loss OF
i'waier from the soil, and if l differ from
him as TO its value, it is because it seems
to me that the experiments were not devils
ed in such a manner as to give reply to
the question asked. The conditions in
volved in plant pot of earth immersed in
water. and those which occur in the field
are vastly different.
We are sorry not to be able to give the
figures of actual experiments which shall
prove that pulverizing the upper soil does
act to conserve the moisture in the field,
because we are not entitled to their first
use, and to do so would violate conf
dence. but these experiments referred TO-,
as well as our own observations upon eX-
periments on the soil, tried for other pur-
poses, shows clearly that loose coating
of earth acts rs a mulch and does conserve
very largely the moisture of field. For
instance; upon a dry spot. a coating of
sand was spread over Il square yard or so,
and IL kernel of corn planted. In the sum-
mer bought, the adjoining corn plants per-
ished, while that mulched with sand neither
wilted, rolled nor showed any other indi.
cations of insufficiency of water Again ::
II plot of land from which the weeds were
removed by hand, rs compared with an
adjoining plot where the surface soil was
kept lightened with the hoe to the depth
of about two inches, showed noticeably
less moisture of the soil through the dry
season, as observed by digging holes to
the sub-soi. Of the crops of corn planted
on these plots, the unhoed crop curlcd its
leaves through lack of moisture, while the
hood crop did not appear to suffer. Again /:
of two boxes, the one filled with sand, and
the water surrounding coming within
several inches of the surface, the evapora-
lion from the surface was very great, and
the water was kept to within short dis
lance of the top. In another box of earth
likewise standing in the water, but with II
coating of two inches of sand, the evapo-
ration was comparatively little. Again
of two pots standing alongside on a green
house bench, the one with the surface
hard, and the other with the surface pull
verified, the former required more frequent
watering than the latter, in order to pre-
serve the life of the plants therein.
Again: in some experiments made 10
test The power of our common angleworm
to convert subsoil and sand into loan,
carried out through last winter in my
study, one of the glasses used contained
compact subsoil; a second glass, clear
sand; and the third, ordinary loan, a half
inch of vegetable matter being originally
placed on the surface of each jar. The
hard soil required II more frequent and
abundant supply of water than did the
loan and less was required for the sand.
And so | might multiply observations
all tending to show that aOhere The sUater
Lerel is brought near the surface of EARTH
the pulveriz4tion of the surface down 10
and including the water soaked portion,
ottentimeS, shows an increase of evapora
ZION. When, however, the pulverized sur
face soil is placed and kept above any per-
manent water level, than the contrary
seems evident--that evaporation is
checked. In general terms, us experience
of the farm shows. Il pulverized surface to
our fields hinders the rise and loss of
moisture from the deeper portions of the
soil although the loss of water is large
from the surface which is itself pulverized.
In some observations on soil lempera-
ture this past summer. found, in every
| trial, that the surface soil was warmer
| than the air, the temperature being taken
early in the morning before the influence
of the sun was to be felt. As dew is only
deposited upon surfaces colder than the
air, cannot believe that under the cir
cnmstances of culture, any moisture from
the air can be deposited in our soil as dew,
and that therefore this, rs II source OF wal
ter addition to our soil, usually, if not al
ways, adduced as one of the effects of
stirring the soil, must be abandoned from
our thought. 1t is very true that under
! laboratory conditions, dry soils do absorb
moisture from the surrounding air. 1t
seems as certain that this absorption has
never been determined for arabic soils
under farm treatment, and that, when ex-
act experiments shall be made, it will be
found that although there may be excep-
tional instances of an accreton of moisture
by dry soils, yet that this fact will not APP
ply 10 the ordinary conditions of soil and
air, as met with on farms, during the
season Of growth in New England
This whole subject of the physics of the
soil is worthy of more full, complete and
exact study, and am very much pleased
to see such an influential and advanced
paper rs the RetTaL NeW Yorker giving it
prominence.-Dr. e. Lewis tSturtevant,
IN RuraL NeeU Yorker.
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