Oxford Democrat. [volume] (Paris, Me.) 1833-1933, 1910-05-24
The Solvent Action Of Rain.

Ihe Solvent Action OF Rain.
HOW 1T AFFECTS THE SALTS OF PLANTS
I-REsULrs OF RECENT EXPERIMENTS
There are two lines of scientific in
vestigatiou now in progress which, whil
entirely independent, have an intimat
relation with each other, as they affsc
good farm practice. These are the
studies of the disposition by plants o
the elements or salts taken up durin
the period of growth. but not found il
the matured plant, on the one hand, ant
the functions Of the mineral salts or asl
content of plants in animal nutrition.
With regard to the latter question, tn
Ohio Experiment Station is CONDUCTING
a series of Investigations the progress o
which has already been once reported
on in popular form. The studies ar,
necessarily somewhat technical, bu
there is much in the subject which ths
Intelligent layman can understand. The
unfavorsble or constipatipg effect of for
age which is deficient in soluble salts
has been noted, and over-ripe and wealth
cred forage seems to owe its injuriously
constipating quality to lack of these
substances. The loss of feeding value
in hay which has been subjected to soak
ing rains is generally recognized. We
also know that the loss is comparatively
slight IL the rain occurs Immediately
after the hay is cut, especially If the
crop is green.
II has been generally believed, how
ever, that the difference in feeding value
between the hay made from green grains
and the straw from ripe grain was due
to the increase in the amount of tough
fiber in the mature plant, and to the
transference of protein and oils from
other portions of the plant to the seed
The loss of total ash content of the
plant, which has been noted by chem
lists, was believed to be due to portion
of the sap returning to the root and car
rying salts in solution which were there
possibly returned to the soil.
Recently elaborate experiments have
been tried by which it has been demon
strated that nearly, If not all, Of the
soluble salts SO lost can be recovered
from the dew and rain which drip from
the plant as it ripeps. In fact, it seems
to be proved that even thriving, grow
ing plants are not immune to the dis
solving action of rain, but give up part
Of their food, held in solution by their
sap, with every thoroughly soaking rain.
These losses seem to be Immediately
made good by the plant from the moist
ened soil, and a general increase OF ash
content takes place up to the completion
of growth and the beginning of ripening.
As the plant natures, the salt seems
to be brought to the surface Of leaves
and stems, where they are crystalized
as the sap evaporates, or are left other
wise exposed and easily dissolved by
rain. IL seems to have been actually
that about ope-half OF the
food value of hay can be soaked out by
rain water, and like loss takes place in
the straw of standing grain while the
seeds are hardening, provided the rain
fall is sufficient.
The experimenters believe that the
mineral constituents of plants at matur-
ity afford little clue to the total amounts
of available plant food actually needed
and taken up by the plant in the course
of the growing season. Under normal
of rainfall the plant seems to
be taking in a great deal more plant
food than is to be found in its complet-
ed structure, differing in this respect
from animal life only in the proportion
cast off and in the method of eliminating
it from the system. Whether it will
next be shown that in the event OF in
sufficient rainfall the plant gives of this
excess of food in the form of dust re-
mains to be seen, but reported expert
ments show a much larger ash content
in plants protected from rain and dew
than in similar plants grown out OF
doors, and it has been frequently noted
that soils used in pot cultures in green
house work are exhausted much more
rapidly than are similar soils producing
similar plants when exposed TO ordinary
atmospheric agencies.
The results of the most recent expert
ments show that about 20 per cent OF
the total nitrogen, 80 per cent of the
phosphoric acid, and IS per cent Of the
potash can be readily removed from
ripening wheat crop by the action of
rain. This discovery gives added force
to the assertion 50 frequently made that
the farmer can afford to take every prac-
ticable precaution to conserve the rain
fall, and should prevent as far as pos
sible all run-off from either naked soil or
that covered by crops. Ii seems further
that the rain which reaches the earth
a mature crop is the best worth
saving Of all the rainfall of the year.
This hypothesis, which seems to have
been demonstrated beyond reasonable
doubt, furnishes an explanation for some
facts often observed on the farm.
For example, it has been noticed that
when a portion of field of hay is raked
and another portion is caught in the
swath and subjected to week OF inter-
mittent rainfall, the second growth
seems to make a more vigorous start
under the hay than on the raked land
alongside. In fact, IL the cut hay is not
thick enough actually to smother the
new growth, the latter will soon so cover
the hay as to hide it, and give the whole
field uniformly green appearance. A
part of this beneficial effect may be due
to shading or mulching the land; but
this can hardly account for the first
yigor of the young shoots which push
up through the hay, for the hay would
not be there except for an excess Of rain
fall, and this would seem to obviats the
need of shade or mulch. 1t will now be
of interest to have careful observations
on the subsequent growth and final
WELD of crops of hay which have started
under weathered hay, as compared with
the growth on ordinary raked stubble.
Another example of rank growth, pos
sibly due to this teaching process, is the
circle of vegetation often seen around
the bases of both hay cocks and grain
shocks when the latter remain long In
the field. Here again We are accustom-
cd to consider the mulching as the prime
cause of the rapid growth, but it now
seems that the drip from the hay or
straw may be an important factor.
The rapid growth Of clover and grass
which has been sown with wheat, which
occurs during the last two weeks pre-
ceding harvest, especially in wet seasons,
is observed by every eastern farmer who
raises these crops together. have al
ways supposed that this was due to the
demands upon soil fertility
and moisture by the maturing wheat, or
possibly to the admission OF moro sun
light as the foliage of the wheat wilted.
It now seems likely that q part OF the
growth is due to the washing back TO
the soil of plant food stored in the ripen-
ing wheat plants.
The interrelation of this whole ques-
tion with that of tho place OF the ash
n II In q