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Cyril G. Hopkins.

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"A crop of fifty bushels would leave only ten bushels as profit;
but, if we could double the yield and thus produce a hundred bushels
per acre, the profit would not be doubled only, but it would be six
times as great as from the fifty bushel crop. In other words, 100
bushels of corn from one acre would yield practically the same
profit as fifty bushels per acre from six acres, simply because it
requires the first forty bushels from each acre to pay for the fixed
charges or regular expense.

"It is not the amount of crop the farmer handles, but the amount of
actual profit that determines his prosperity. It requires profit to
build the new home or repair the old one, to provide the home with
the comforts and conveniences that are now to be had in the country
as well as in the city; to send the boys and girls to college; to
provide for the expense of travel and the luxuries of the home."

Percy stopped himself with an apology.

"I hope you will pardon me, Miss West. I forget that this subject
may be of no interest to you, and I have completely monopolized the
conversation."

"I am glad you have told me so much," she replied. "I am deeply
interested in what you have been saying. I never realized that
agriculture could involve such very important questions in regard to
our national prosperity. I only know that our farm has furnished us
with a living but there has been very little of what you call
profit. We children could never have gone away to school except that
we were enabled to take advantage of some unusual opportunities. My
brother almost earned his expenses as commissary in a boarding club
at college. He felt that he could not come home for Thanksgiving
because he had a chance to earn something and I have missed him so
much. Most farmers get barely enough from their farms in these parts
to furnish them a modest living and pay their taxes."

"That reminds me of your statement that farming is the last thing
that you would expect anyone to undertake. In a large sense that is
in accordance with the history of all great agricultural countries.
After the great wave of easy spoilation of the land has passed, and
the farmers reach a condition under which they need most of what
they produce for their own consumption, the parasites are themselves
forced to produce their own food. The lands become divided into
smaller holdings and the agricultural inhabitants increase rapidly
in proportion to the urban population which must depend upon the
profits from secondary pursuits for a living. Thus ninety-five per
cent. of the three hundred million people of India belong
principally to the agricultural classes, and the farms of India
average about two to three acres in size. Farming there is in no
sense a profit-yielding business, but it is only a means of
existence. The people live upon what they raise, so far as they can,
although, as you must know, India is almost never free from famine.
In Russia, the situation is but little better, for famine follows if
the yield of wheat falls two bushels below the average. Special
agents of the Bureau of Statistics of the United States Department
of Agriculture report that at least one famine year occurs in each
five year period, and sometimes even two; that the famine years are
so frequent they are recognized as a permanent feature of Russian
agriculture."

"But couldn't those poor starving people do some other kind of work
and thus earn a better living?" asked Adelaide.

"No. Agriculture is the only hope," said Percy. "The soil is the
breast of Mother Earth, from which her children must always draw
their nourishment, or perish. It is the 'last thing,' as you truly
said. Aside from hunting and fishing, there is no source of food
except the soil, and, when this is insufficient for the people who
produce it in the country, God pity the poor people who live in the
cities. But let us not talk of this more. I ought not to have taken
up the time of our ride through this beautiful scenery with a
subject which tends always toward the serious. The leaves are all
gone in New England, but here they have only taken on their most
beautiful colors. 'What is so rare as a day in June?' could now well
be answered, 'a day in November in Piedmont, Virginia.'"

"Do you know if your father received a letter for me from the
chemist to whom I sent the soil samples?"

"Yes, it came in Wednesday's mail, and there is a letter from the
University of Illinois and two others that Grandma says must be from
a lady. Papa says he is anxious to know what results would be found
in the chemist's report. May I listen while you tell papa about it?
Indeed, I am extremely interested to know if anything can be done to
make our farm produce such crops as it used to when grandmother was
a little girl."

"Still I fear you will find it a very tiresome subject," said Percy.
"It is, as a rule, not an easy matter to adopt a system of permanent
improvement on land that has been depleted by a century or more of
exhaustive husbandry. but you will be very welcome not only to
listen but to counsel also. My mother can measure difficulties in
advance better than most men; and I believe it is true that women
will deliberately plan and follow a course involving greater
hardship and privation than men would undertake. I cannot conceive
of any man doing what my mother has done for me."

Adelaide glanced at Percy as he spoke of his mother. Something in
his words or voice seemed to reveal to her a depth of feeling, a
wealth of affection akin to reverence, such as she had never
recognized before.


CHAPTER XXIX

THE ULTIMATE COMPARISON


WILKES was at the side gate to meet Adelaide and Percy, and the
grandmother stood at the door as they reached the veranda.

"Lucky for us you got back before the Thanksgiving scraps are all
gone," she said to Percy, "but I suppose even our Thanksgiving fare
will be poor picking after you've been living in Washington and
Boston."

"Even the Thanksgiving dinner on the boat was not equal to this,"
said Percy, as they sat down to the table loaded with such an
abundance of good things as is rarely seen except on the farmer's
table. The "scraps," if such there were, had no appearance of being
left-overs, and there was monster turkey, browned to perfection and
sizzling hot, placed before Mr. West ready for the carving knife.

Percy had opened the letter from the chemist, but said to Mr. West
that it would take him an hour or more to compute the results to the
form of the actual elements and reduce them to pounds per acre in
order to make possible a direct comparison between the requirements
of crops, on the one hand, and the invoice of the soil and
application of plant food in manure and fertilizers, on the other
hand.

"Please let me help you make the computations," said Adelaide, much
to the surprise of her parents, who knew that she took no interest
in affairs pertaining to farming. "I like mathematics and will
promise not to make any mistakes if you will tell me how to do some
of the figuring."

"Thank you," said Percy. "With your help it will take only half the
time that I should require alone."

This proved to be correct, for in half an hour after supper they had
the results in simplified form. Even the mother and grandmother
joined the circle as Percy began to discuss the results with Mr.
West

"Now here is the invoice," said Percy, "of the surface soil from an
acre of land where we collected the first composite sample, - the
land which you said had not been cropped since you could remember.
This soil contains plant food as follows:

1,440 pounds of nitrogen
380 pounds of phosphorus
15,760 pounds of potassium
3,340 pounds of magnesium
10,420 pounds of calcium

"I'd like to know how these amounts compare with what your Illinois
soil contains," said Mr. West.

"We have several different kinds of soil in Illinois," replied
Percy. "The common corn belt prairie soil is called brown silt loam.
It contains, as an average, 5000 pounds of nitrogen and 1200 pounds
of phosphorus, or nearly four times as much of each of those
elements as this Virginia soil which you say is too poor to
cultivate.

"I wrote to the Illinois Experiment Station before I left Washington
to see if I could get the average composition of the heavier prairie
soil, which occupies the very flat areas that were originally
swampy, and one of the letters you had received for me gives 8000
pounds of nitrogen and 2000 pounds of phosphorus as the general
average for that soil. That is our most productive land, and it
contains about five times as much of these two very important
elements as your poorest land.

"Our more common Illinois prairie contains about 35,000 pounds of
potassium, 9,000 pounds of magnesium, and I 1,000 pounds of calcium.
This is more than twice as much potassium and nearly three times as
much magnesium as in your poorest land, but the calcium content is
about the same in your soil as in ours. However, as you will
remember, your soil is distinctly acid and consequently markedly in
need of lime, the magnesium and calcium evidently being contained in
part in the form of acid silicates with no carbonates; whereas, our
brown silt loam is a neutral soil and our black clay loam contains
much calcium carbonate, the same compound as pure limestone."

"I am anxious to know about our best land," said Mr. West. "What
did the chemist find in the soil from the slope where we get the
best corn after breaking up the old pastures?"

"He found the following amounts in the surface soil," said Percy.

800 pounds of nitrogen

1,660 pounds of phosphorus

34, 100 pounds of potassium

8,500 pounds of magnesium

13,100 pounds of calcium

"Rich in everything but nitrogen," Percy continued, "richer than our
common prairies in phosphorus and calcium, and nearly as rich in
potassium and magnesium; but very, very poor in nitrogen. Legume
plants ought to grow well on that land, because the minerals are
present in abundance, and, while lack of nitrogen in the soil will
limit the yield of all grains and grasses, there is no nitrogen
limit for the legume plants if infected with the proper
nitrogen-fixing bacteria, provided, of course, that the soil is not
acid. You will remember, however, that even this sloping land is
more or less acid, although here and there we found pieces of
undecomposed limestone. With a liberal use of ground limestone, any
legumes suited to this soil and climate ought to grow luxuriantly on
those slopes."

"That reminds me that we are greatly troubled with Japan clover on
those slopes," said Mr. West. "Of course it makes good pasture for a
few months, but it doesn't come so early in the spring as blue grass
and it is killed with the first heavy frost in the fall. We like
blue grass much better for that reason, but when we seed down for
meadow and pasture, the Japan clover always crowds out the timothy
and blue grass on those slopes."

"And when you plow under the Japan clover, you get one or two good
crops of grain," said Percy, "because this clover has stored up some
much needed nitrogen and the soil is rich in all other necessary
elements. Have you ever tried alfalfa on that kind of land? That is
a crop that ought to do well there, especially if limestone were
applied."

"Yes, I have tried alfalfa," replied Mr. West, "and I tried it on a
strip that ran across one of those steep slopes; but it failed
completely, and, as I remember it, it was poorer on that hillside
than on the more level land."

"Did you inoculate it?" Percy asked.

"Inoculate it? No. I didn't do anything to it, but just sow it the
same as I sow red clover."

"What does it mean to inoculate it?" asked Adelaide.

"It means to put some bugs on it," said the grandmother; "some germs
or microbes, or whatever they are called. Don't you remember,
Adelaide, that I told you about that when I read it in the magazine
a while ago? Don't you remember that somebody was making it and a
man could carry enough in his vest pocket to fertilize an acre and
he wanted $2 a package. Charles said that $1.50 a hundred was more
than he could afford to pay for fertilizer, and he didn't care to
pay $2 for a vest pocket package. Isn't that the stuff, Mr.
Johnston?"

"It listens like it, as the Swedes say," said Percy, "but the
advertisements of these germ cultures put out by commercial
interests are usually very misleading. The safest and best and least
expensive method of inoculating a field for alfalfa is to use
infested soil taken from some old alfalfa field or from a patch of
ground where the common sweet clover, or mellilotus, has been
growing for several years. I saw the sweet clover growing along the
railroad near Montplain, and there is one patch on the roadside
right where - when you enter the valley on the way to the station."

"Right where Adelaide smashed that nigger's eye with her heel and
helped Mr. Johnston capture them both," broke in the grandmother.
"That's the only good thing I can say for her peg heeled shoes."

Adelaide colored and Percy now understood what had been a puzzle to
him.

"The same bacteria," he went on quickly, "live upon both the sweet
clover and the alfalfa, or at least they are interchangeable. These
bacteria are not a fertilizer in any ordinary sense, but they are
more in the nature of a disease, a kind of tuberculosis, as it were;
except that they do much more good than harm. They attack the very
tender young roots of the alfalfa and feed upon the nutritious sap,
taking from it the phosphorus and other minerals and also the sugar
or other carbohydrates needed for their own nourishment, since they
have no power to secure carbon and oxygen from the air, as is done
by all plants with green leaves. On the other hand, these bacteria
have power to take the free nitrogen of the air, which enters the
pores of the soil to some extent, and cause it to combine with food
materials which are secured from the alfalfa sap, and thus the
bacteria secure for themselves both nitrogen and the other essential
plant foods. The alfalfa root or rootlet becomes enlarged at the
point attacked by the bacteria, and a sort of wart or tubercle is
formed which resembles a tiny potato, as large as clover seed on
clover or alfalfa, and, singularly, about as large as peas on
cowpeas or soy beans. On plants that are sparsely infected, these
tubercles develop to a large size and often in clusters. While the
bacteria themselves are extremely small and can be seen only by the
aid of a powerful microscope, the tubercles in which they live are
easily seen, and they are sufficient to enable us to know whether
the plants are infected."

"I wish you would tell me the difference between the words
inoculated and infected," said Adelaide.

"Inoculated is used in the active sense and infected in the
passive," said Percy. "Thus the red clover growing in the field is
infected if there are tubercles on its roots, although it may never
have been inoculated; and we inoculate alfalfa because it would not
be likely to become infected without direct inoculation."

"Under favorable conditions," continued Percy, "these bacteria
multiply with tremendous rapidity, somewhat as the germs of small
pox or yellow fever multiply if allowed to do so. A single tubercle
may contain a million germs which if distributed uniformly over an
acre would furnish more than twenty bacteria for every square foot."

"There, Charles," said the grandmother, "wouldn't a vest pocketful
of those bugs or germs be a big enough dose for one acre?"

"Well, but they're not a fertilizer, Mother," said Mr. West, "and
besides Mr. Johnston says it is better to use the infected sweet
clover soil and there is no need of paying $2 an acre for something
we knew nothing about, and especially on land that is not worth more
than $2 an acre."

"I don't care what it's worth," she replied, "some of it cost your
grandfather $68 an acre, and it will never be sold for any $2, while
I have any say so about it."

They waited for Percy to proceed.

"The individual bacteria are very short-lived," he continued, "and
products of decay soon begin to accumulate in the tubercles. These
products contain, in combined form, nitrogen which the bacteria have
taken from the air, and in this form it is taken from the tubercles
and absorbed through the roots into the host plant and thus serves
as a source of nitrogen for all of the agricultural legumes.

"It should be kept in mind, of course, that the red clover has one
kind of nitrogen-fixing bacteria, that the cowpea has a different
kind, and that the soy bean bacteria are still different, while a
fourth kind lives on the roots of alfalfa and sweet clover."

"How much infected sweet clover soil would I need to inoculate an
acre of land for alfalfa?" asked Mr. West.

"If the soil is thoroughly infected, a hundred pounds to the acre
will do very well if applied at the same time the alfalfa seed is
sown and immediately harrowed in with the seed. If allowed to lie
for several hours or days exposed to the sunshine after being spread
over the land the bacteria will be destroyed, for like most
bacteria, such as those which lurk in milk pails to sour the milk,
they are killed by the sunshine."

" That's right," said the grandmother. "That's the way to sterilize
milk pails and pans and crocks. I like crocks better than pans. They
don't have any sort of joints to dig out."

"Of course," continued Percy, "a wagon load of infected soil will
make a more perfect inoculation than a hundred pounds, and where it
costs nothing but the hauling it is well to use a liberal amount."

"How deep should it be taken?" asked Mr. West.

"About the same depth as you would plow. The tubercles are mostly
within six or eight inches of the surface. The bacteria depend upon
the nitrogen of the air and this must enter the surface soil.
Sometimes in wet weather the tubercles can be found almost at the
surface of the ground, and when the ground cracks one can often find
tubercles sticking out in the cracks an inch or two beneath the
surface but protected from direct sunshine.

"These bacteria have power to furnish very large amounts of nitrogen
to such a crop as alfalfa. The Illinois Station reports having grown
eight and one-half tons of alfalfa per acre in one season. It was
harvested in four cuttings. The hay itself was worth at least $6 a
ton above all expenses, which would bring $51 an acre net profit for
one year. Of course this was above the average, which is only about
four and one-half tons over a series of several years. But suppose
you can save only three tons and get $6 a ton net for it, as you
could easily do by feeding it to your cattle and sheep. That would
bring $18 an acre or six per cent. interest on $300 land. I am
altogether confident that this could be done on your sloping
hillsides, with their rich supplies of phosphorus and other mineral
foods, provided, of course, that you use plenty of ground limestone
and thoroughly inoculate the soil."

"Well, I shall certainly try alfalfa again," said Mr. West, "and if
I can grow such crops of alfalfa as you think on the hillsides, I
can have much more farm manure produced for the improvement of the
rest of the land. By the way what did that chemist find in that
sample you took of the other land where it does not wash so much as
on the steeper slopes."

"He found the following:

1,030 pounds of nitrogen
1,270 pounds of phosphorus
16,500 pounds of potassium
7,460 pounds of magnesium
16,100 pounds of calcium

"Well, the phosphorus is not so low," said Mr. West.

"Fully equal to that in our $150 Illinois prairie," replied Percy,
"and again the calcium is more than ours, with magnesium not far
below, and potassium half our supply. Nitrogen is plainly the most
serious problem on most of this farm, and limestone and legumes must
solve that problem if properly used."

"Do you think this land could be made as valuable as the Illinois
land just by a liberal use of limestone and legumes?" asked
Adelaide.

"I should have some doubt about that," Percy replied. "Your very
level uplands that neither lose nor receive material from surface
washing are very deficient in phosphorus and much poorer than ours
in potassium and magnesium; and your undulating and steeply sloping
lands are more or less broken, with many rock outcrops on the points
and some impassable gullies, which as a rule compel the cultivation
of the land in small irregular fields. A three-cornered field of
from two to fifteen acres can never have quite the same value per
acre as the land where forty or eighty acres of corn can be grown in
a body with no necessity of omitting a single hill. Then there is
some unavoidable loss from surface washing, so that to maintain the
supply of organic matter and nitrogen will require a larger use of
legumes than on level land of equal richness. In addition to this is
the initial difference in humus content. This is well measured by
the nitrogen content. While your soil contains eight hundred pounds
of nitrogen on the steeper slopes and one thousand pounds on the
more gently undulating areas, ours contains five thousand pounds in
the brown silt loam and eight thousand pounds in the heavier black
clay loam. This means that our Illinois prairie soil contains from
five to ten times as much humus, or organic matter, as your best
upland soil. To supply this difference in humus would require the
addition of from four hundred to eight hundred tons per acre of
average farm manure, or the plowing under of one hundred to two
hundred tons of air-dry clover. This represents the great reserve of
the Illinois prairie soils above the total supplies remaining in
your soils.

"Our farmers are still producing crops very largely by drawing on
this reserve. Of course most of this great supply of humus is very
old. It represents the organic residues most resistant to
decomposition; and, where corn and oats are grown exclusively, the
soil has reached a condition on many farms under which the
decomposition of the reserve organic matter is so slow that the
nitrogen liberated from its own decay and the minerals liberated
from the soil by the action of the decomposition products are not
sufficient to meet the requirements of large crops, and for this
reason alone some of our lands that are still rich are said to be
run down; but they only require a moderate use of clover or farm
manure or other fresh and active organic matter to at once restore
their productiveness to a point almost equal to the yields from the
virgin soil. Some Illinois farmers who have discovered this apparent
restoration have jumped to the conclusion that they have solved the
problem of permanently maintaining the fertility of the soil; and I
judge from a remark made by the Secretary of Agriculture that some
Iowa farmers have the same mistaken notions.

"These fresh supplies of active organic matter serve primarily as
soil stimulants, hastening the liberation of nitrogen from the
organic reserve and of minerals from the inorganic soil materials.

"Where one of the Eastern farmers has managed a farm under the
rotation system with the occasional use of clover or light
applications of farm manure, - where this has been continued until
the great reserve is largely gone, and the phosphorus supply greatly
depleted, then the land is truly run down, but not until then.

"Finally, land-plaster and quick-lime, still more powerful soil
stimulants, are often brought into the system to bring about a more
complete exhaustion of the soil reserves, and lastly the use of
small amounts of high-priced commercial fertilizers serves to put
the land in suitable condition for ultimate abandonment."

"Do you mean that commercial fertilizers injure the soil?" asked Mr.
West.

"Well, to some extent they injure the soil because they tend to
destroy the limestone and increase the acidity of the soil, and also
because they contain more or less manufactured land-plaster and thus
serve as soil stimulants; but the chief point to keep in mind
concerning the use of the common so-called complete commercial
fertilizer is that they are too expensive to permit their use in
sufficient quantities to positively enrich the soil. Thus the farmer
may apply two hundred pounds of such a fertilizer at a cost of $3.00
an acre, and then harvest a crop of wheat, two crops of hay, pasture
for another year or two, plow up the grounds for corn, apply another
two hundred pounds for the corn crop, follow with a crop of oats,
and then repeat. He thus harvests five crops and pastures a year or


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Online LibraryCyril G. HopkinsThe Story of the Soil; from the Basis of Absolute Science and Real Life, → online text (page 13 of 23)