1846. THE CULTIVATOR. 177 
MANURING- BY GREEN CROPS. 
Can land be improved merely by plowing- in the 
crops which grow in it? 
Suppose land to be in clover; which will most im¬ 
prove the soil, or conduce to the product of the succeed¬ 
ing crops, plowing in the entire growth of clover, or 
feeding it off Avith stock? 
At what stage should a green crop be plowed in to 
obtain from it the greatest benefit? 
Some have doubted whether land can be improved by 
its own products alone. The idea with those who en¬ 
tertain this doubt, seems to be that every ingredient of 
the vegetable structure comes originally from the soil, 
and that hence no principle of fertility can be added to a 
given extent of soil simply by the decay of vegetation 
which it has produced. Without attempting to argue 
this point in detail, it is sufficient, perhaps, to advert to 
the well-known fact that the fertility of forest lands in¬ 
creases as long as the growth of wood continues. 
It is related that Van Helmont planted a stalk of wil¬ 
low in a box containing a quantity of earth. He care¬ 
fully dried and weighed the earth before planting the 
twig. He Avatered it with distilled Avater only. After 
several years, he took out the willow which had attain¬ 
ed an increased weight of many pounds, dried the earth 
as before, weighed it, and ascertained that it had lost 
only an ounce or two of its original weight.* 
The fact that vegetables do derive a part of their 
substance from the atmosphere, admits, at least of no 
reasonable doubt; but certain kinds of plants are be¬ 
lieved to draw their food from the atmosphere in great¬ 
er proportion than others. It seems reasonable to be- 
lie\*e that those substances which have once formed 
plants, are capable, by decomposition, of contributing 
to the growth of other plants whose nature and compo¬ 
sition are more or less similar. 
It has been ascertained that carbon enters largely into 
the structure of plants—it is, indeed, next to water, the 
chief element of their composition.f It is taken up 
in the form of carbonic acid, both through the leaves 
and the roots. Those plants Avhieh take the largest pro¬ 
portion of their food from the air through the leaves, 
are the broad-leaved kinds. By cultivating those of 
this description, and depositing their substance in the 
soil, we can increase the elements of fertility—that is, 
we can draw from the air and concentrate in the soil, 
matter which will supply food to other plants. 
So much for our first question. In regard to the 
second, we incline to the opinion from evidence de¬ 
rived from experience and observation, and considera¬ 
ble inquiry, that it is better to feed off clover than to 
plow it in. We believe that the best crops are obtained 
where the clover is depastured. This subject has been 
brought up for discussion at several of our agricultural 
meetings, and the opinion expressed by nearly all far¬ 
mers who have had practical acquaintance with it, was 
in agreement with our own. Col. Cost, member of 
the Assembly from Ontario, and an extensive and judi¬ 
cious farmer, stated that he had practised plowing in 
clover, and had observed the results thus produced com¬ 
pared with those where it had been fed off, and he gave 
a decided preference to the latter course. The experi¬ 
ence of Gen. Harmon, of Wheatland, well known as 
one of our most successful wheat-farmers, has also, 
we are authorized to say, induced him to form the same 
opinion. He has noticed that his wheat crop is always 
better where clover has been depastured. 
We are not aware of many experiments having been 
* The writer is unable to refer particularly to this experiment, 
but is confident that the facts are stated in general terms. 
t The substance of plants chiefly consists of woody fibre, starch, 
and gluten. Woody fibre and starch, and also gum and sugar, 
consist of carbon and water only. Thirty-six pounds of carbon 
and thirty-six pounds of water, form seventy-two pounds of woody 
fibre. Thirty-six pounds of carbon and forty-five pounds of water, 
form eighty-one pounds of dry starch or gum. Thirty-six pounds 
of carbon and forty-nine and a half pounds of water, form eighty- 
five and a half pounds of loaf-sugar or sugar-candy,—and thirty- 
six pounds of carbon and twenty-seven pounds of water form 
sixty-three pounds of humic acid —Johnston 
made expressly for the purpose of testing this point, 
though its importance is such as to render the most 
careful experiments necessary, and we would suggest 
this to agricultural societies as one of the subjects to 
which their attention shoukfbe directed. 
We recollect having read an account of an experi¬ 
ment made by the late Gen. Harrison, of Ohio. He 
had a field of clover consisting of several acres—the 
soil of clayey loam, and of uniform character. He di¬ 
vided it into two parts, one of which was pastured, 
chiefly with cattle, and on the other the growth of clo¬ 
ver Avas plowed in. In the autumn, the pastured por¬ 
tion was plowed, and both parcels Avere sown to wheat. 
The wheat was best on the part which had been pas¬ 
tured, as were also the two succeeding crops, consist¬ 
ing, if we mistake not, of oats and clover. 
Various causes are assigned for the effects above men¬ 
tioned. 1. It is said that by burying in the soil a mass 
of vegetation Avhile it is filled with sap and juices, a 
sourness is produced which is hurtful to succeeding 
crops. 2. In some instances where a considerable 
quantity of clover has been ploAved in, its effect is 
thought to have been to make the soil too “ hovery,” 
or ee puffy,” as it is variously called—that is it become s 
too loose at the bottom of the furrow and the roots of 
the wheat do not obtain a sufficiently firm hold. 
That sourness is actually caused by the fermentation 
of a large mass of green clover or other vegetation, 
does not seem improbable. The sap contained in the 
stalks and leaves may be forced by fermentation into 
acetic acid, and the sugar and starch be turned to vinegar. 
Every one may have noticed that a pile ol green weeds 
or green grass, becomes after a time actually sour —the 
acid may be perceived both by smell and taste—and we 
are unable to see why the same effect should not take 
place when a hea\'y crop of clover is turned in Avith the 
plow. At all events, the effects of the practice are such 
that many farmers declare they would prefer having the 
clover cut and carried off the land rather than that it 
should be turned in green. 
Mr. Vedder, of Geneva, informs us that he formerly 
plowed in clover, but that he has latterly discontinued the 
practice. He is of opinion that the chief value is in the 
root of the plant, and he states that he has obtained 
better crops where the clover has been cut and the 
stubble only plowed in, than by plowing in the green 
tops. Gen. Harrison, also, in explaining the results 
of the experiment above mentioned, suggests that the 
principal amelioration of the soil is by the roots. They 
may produce a favorable effect in several ways. Where 
the soil is too compact, they make it more friable by 
dividing and opening it, and the decomposition of the 
roots themselves furnishes a large amount of matter. 
We will suggest another mode also by which the 
roots improve the soil. It is known that plants exert a 
vital action on the soil. It is by this principle of vi¬ 
tality that they are able to reduce the various substan¬ 
ces of which they are formed, into food on which they 
can subsist. Inexplicable as is this mysterious power, 
it must be great; for by its exercise the hardest flints 
and the other mineral elements which enter into the 
vegetable structure, are perfectly dissolved, are taken 
up and made to perform their several offices in the 
tissues. Perhaps no plant is more remarkable for this 
action than clover. Some idea may be formed of it 
by observing the effect produced when its roots are 
brought in contact with rocks or stones. Under this 
vital energy, through the agency of light, heat, air, and 
moisture, the solid rock is made to crumble, and gradu¬ 
ally to Avear away. Now may not this action of the 
roots tend to bring the earthy matters composing the 
soil into a state more favorable to the support of other 
plants? May not the mineral elements be thus ren¬ 
dered more easily soluble and available to other crops? 
It may be said that the sourness before spoken of, can 
be avoided by allowing the clover crop to ripen and 
die before it is plowed in. This is probably true, and 
it has been tried in some cases, but still preterence 
has been given to the practice of feeding off the crop. 
The fact upon the whole seems probable, that there are 
