April 1957 — Vol. 38, No. 4 — On Using Soil Wisely
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THROUGH MILLIONS of years nature built
up a balance between animal, vegetable and mineral life. She
tied the mixture in place on the earth's surface by the interlacing
of grass roots on our prairies and tree roots in our forests.
The leaves she discarded in autumn became part of the soil
that produced them.
But we humans came and broke the prairies and cleared away
the forests. We upset the balance of nature. Today, our earth
is sick.
We had an abundance of resources when our forefathers came
to live in this country. We acted like the people at Alice
in Wonderland's mad tea—party: when the tea and cakes
were exhausted at their places the Mad Hatter and the Match
Hare moved on to the next seats. When Alice asked what would
happen when they came to the end of new seats, the March Hare
changed the subject.
All through the ages we have struggled to wrest the land
from nature, and our conquest has been disastrous. Nature
does not submit willingly to conquest, and today you may read
the dismal story of our "victory" in washed—out farm
land, sand—blown pastures, and depopulated townships.
We don't need to go back for examples to the deserts of Asia
Minor, where 500 cities once flourished on a good agricultural
base; we can see the beginnings of land exhaustion in an hour's
drive from any town in Canada.
It would be unfair to blame our early settlers, as is so
often done. They lacked the scientific knowledge we have.
It may have been their only way of self—preservation
to hew down trees so as to reach the soil on which to grow
crops. There was a time when people believed in the agricultural
destiny of forest land. And there were times in Canada's early
history when food was hard to get.
That belongs to the past. Water and wind have flayed the
skin off the unprotected earth, and that this has continued
up to our own time is chargeable to our neglect and not to
the actions of out forefathers.
Some of our tilled land should never have been broken to
the plough, and we should return it to trees or grass. Some
of our farm land needs rebuilding organically if it is to
continue providing its owners with an adequate level of comfort.
Some needs attention just to preserve it from destruction.
All of our land needs careful management.
And what has this to do with people who live in cities?
Merely this: a prosperous agriculture makes possible successful
business, thriving trading centres, a high level of industrial
activity, and health.
It was thirty years ago, around 1926, that articles in the
popular press about soil erosion attracted wide public attention.
Then followed the droughts of the 1930's, making every newspaper
reader conscious of the damage being done to our soil and
our people. Erosion moved to the forefront of interest when
President Roosevelt established a soil erosion service in
the United States Department of the Interior in 1933 with
a mandate to stop erosion.
Human erosion
Just what, in plain terms, does this deterioration of land
mean to us? One result of lack of conservation is a lowered
level of living and the development of human erosion to be
seen in various deficiency diseases and hidden hunger. It
is conceivable that if wastage of land goodness continues
we shall be faced, not with a struggle for markets, but with
a struggle for food.
Health is so important to us that we should be well advised
to spend relatively more on knowing our soils and seeing that
they are healthy, and relatively less on our illnesses which
are frequently merely the outward sign of an often unrealized
soil deficiency.
In considering health it is misleading to separate man,
animals and plants. All are part and parcel of the same nutrition
cycle which governs ail living cells. The earth's green carpet
is the source of the food consumed by live—stock and
mankind.
This all—embracing idea of the unity of nature is a
comparatively new field of study. A report of a select committee
on conservation to the Ontario Government in 1950 said that
there were nine stations in the United States investigating
the relationship between the soil and human health, while
"in Canada, very little has been done on this important subject."
Science has now turned its eyes in a direction that may
lead to betterment of the human race. Plants serve as intermediaries,
drawing chemicals out of the earth into their sap and changing
them into compounds that can be used by animals for building
flesh, blood and bones. In their effort to aid in the production
of food of high nutritional value, scientists are pursuing
a noble objective.
Conserving soil
Conservation is the wise use without waste of our natural
resources. It is not the job of scientists alone, nor of farmers
alone, but of all of us.
On the farmer's field, conservation consists of mechanical
methods, such as ploughing, to slow down the run—off
of water, and chemical methods, to incorporate materials that
build up the fertility of the soil. In the details of these
practices, the farmer receives guidance from the Department
of Agriculture at Ottawa, his provincial department, and his
agricultural representative.
When land loses its fertility there are some simple steps
to be taken: the addition of fertilizer and organic matter;
the growth of sod crops; the adoption of rotations. To save
soil it is necessary to hold rainfall, retard the flow of
water, check wind erosion, and apply vegetative and mechanical
controls.
Most conservation practices are simple. They consist only
in adapting regular farming operations to nature's way. We
don't have to turn our country over to grass and trees, but
we do have to use grass and trees in the proper places and
at the right times.
Hill—tops are vulnerable, because that is where water
starts running. An effective cover of grass or trees to hold
and absorb rainfall at the upper edge of a slope is the start
of erosion control and flood control.
Just how serious is what we are talking about? It is one
of the great problems of the day.
Conservation—minded authorities in central Canada are
now surveying for reclamation and protection the land on which
the first white settlers set up their homes in 1842, only
115 years ago.
Dr. Georges Maheux, of Laval University, told a meeting
of the Royal Society last June that Canada needs a conservation
policy to put an end to the "reckless squandering" of natural
resources.
Dr. B. T. Dickson, who received his early training at Queen's
and McGill universities, said to the American Academy for
the Advancement of Science: "Today we know that Malthus was
just ahead of his time, and we have to ask ourselves whether
adequate food requirements of people can be provided from
present sources with all the technologic experience available
to us."
And Dr. Stanley A. Cain, botanist, warned that men everywhere
must face the dual problems of the conservation of natural
resources and the limitation of population "or continue along
the path, at an ever—accelerating rate, toward self—destruction."
One third bas been lost
We have passed the stage of looking upon plants and vegetation
as inexhaustible resources, but we do not yet fully realize
how perishable the earth's goodness can be. In the Vosges
mountains soil that has been washed down to the valley during
the growing season is carefully shovelled into baskets during
fall and winter and carried on the backs of men to be replaced
on the tilled ground. Authorities say that the United States,
which founded its civilization on nine inches of top—soil,
has lost a third of this soil.
There is, however, no need to take a gloomy view; there
is no excuse for throwing up our hands. We have been sufficiently
warned to prevent us from dismissing the subject as unworthy
of attention, but active attention it must have.
What we seek from the land is that it provide the base of
the highest possible standard of living for the people of
Canada. We are inclined, in these technological rimes, to
rely upon our ingenuity to make up for our wastefulness. But
even technologists must eat, and we are not yet assured that
essential food needs can be supplied synthetically. In any
event, if we have failed to save our natural sources of food,
what assurance have we that we shall make wise or effective
use of chemical sources?
What we can do is use technology to expand out soil resources
by increasing the soil's productivity.
Some evidence
Much of our land is marred by deep scars, plain for all
to see as the evidence of neglect of conservation measures.
But there is other evidence, visible only to the observing
person: the hundreds of acres of stunted crops resulting from
loss of fertility from the soil.
Water erosion occurs chiefly on sloping land, removing the
soil in sheets (sheet erosion), or cutting it with many small
streamlets (rill erosion), or gashing out deep gullies (gully
erosion). Wind erosion occurs on both sloping and level land.
Both result from removal of vegetative cover.
If you dip up a pail of water that has flowed off a cultivated
field and let the mud settle you will find as much as ten
to 25 per cent of the volume to be soil. To take a measured
example: the maximum flood flow in a section of the Appalachian
region during a little over three years was only six cubic
feet per second per square mile from forested watersheds;
from abandoned agricultural land the flow was 403 cubic feet
per second per square mile, and from gullied pasture land
785 cubic feet.
In another experimental section still more dramatic evidence
of loss has been obtained. With an average annual precipitation
of 35 inches, on a slope of eight per cent, the loss of soil
from a clean—tilled field was 69 tons a year; from a
field with dense cover provided by a thick—growing crop,
the loss of soil averaged only .3 of a ton. The soil
scientists estimate that on the cleantilled field it will
take only 16 years to remove seven inches of top—soil,
while to wash away seven inches from the protected field would
take 3,900 years.
These examples are not of merely academic interest, but
throw into highlight a real and vital problem. A soil erosion
and land use survey of 22,000 acres in Durham County, made
by the Ontario Agricultural College and the Central Experimental
Farms, gave statistical form to a sample of the present state
of once—good farm land. Sixty—three per cent of
the area was eroded in some degree. This is divided: 27 per
cent slightly; 24 per cent moderately; six per cent severely,
and six per cent very severely eroded.
The damage of erosion does not end at the farm. Dams, reservoirs,
navigable streams, irrigation ditches and power plants are
reduced in efficiency by sedimentation. Take as an example
a power—house reservoir in Virginia: its capacity was
reduced in 26 years from 4,000 acre—feet to 780 acre—feet,
a loss of 80 per cent.
A drop of rain
The raindrop has been presented to us in song and story
since out childhood as a friend. Perhaps this has made it
difficult for us to believe that it would destroy our land.
Every falling raindrop that strikes the bare ground acts
as a miniature bomb. It splashes soil into the air at its
point of impact. It holds the soil in suspension to run off
with the surface water. It puddles the surface, forming seals
that practically waterproof the land.
Surface sealing causes poor aeration, destroys worm life,
and interferes with microbial action within the soil. Splash
erosion may wash out and float away the light organic materials
that are so important to soil health. Says the report to the
Ontario Legislature:"A one—inch rain can move 100 tons
of soil per acre."
The importance of the impact of raindrops is confirmed by
tests at the Central Experimental Farm, Ottawa. The distribution
and intensity of individual rainstorms are much more important
factors than the total rainfall. In one growing season there
was a loss of 28.7 tons of soil per acre on a corn plot on
a ten per cent slope, while next year, with an almost identical
total rainfall but more spread out, the loss from the same
plot was only 2.3 tons per acre. In a test elsewhere it was
found that during periods of most intense rain the surface
flow from barren ground amounted to between 75 and 95 per
cent of the rainfall.
Abusing the land
This is not to say that all the blame for soil erosion should
be placed upon the lowly raindrop. It is when the raindrop
strikes a place where human cultivation has removed nature's
protective mantle that trouble occurs.
Some of our cut—over forest land is unfit for farming,
inhabited only by stranded families squeezing a bare existence
out of eroded soil, and no protective device will make it
profitable for agriculture. Some land has been unwisely drained,
and farms on that land, even if operated under the best possible
management, would fail to provide the necessities of life.
Some pasture land has been over—grazed, so that drought
and water erosion take a heavy toll. It is true that millions
of native big game mammals once existed on the western American
plains, but their herds were part of a complex system of checks
and balances that kept their numbers from getting out of hand.
Says William Vogt pungently in his book Road to Survival:
"Nature red in tooth and claw was a far kinder nature than
that of modern man, who has destroyed indispensable environment
beyond any hope of repair."
Misuse of soils is the product of ignorance or indifference.
The first should be remedied by efforts now being made to
survey our soil, and the second may be cured by education
and, if necessary, regulation.
Aware of the need for soil information, Canada established
a national soil survey committee about 1941. The provinces
conduct intensive surveys of counties or watersheds or other
divisions. Several conservation surveys have been published
by the Ontario Department of Planning and Development, the
outcome of joint action by the Ontario Agricultural College
and the Dominion Experimental Farm Service. Early this year
the Senate set up a 26—man committee charged with a widespread
study of land use in Canada, a job described in the Chamber
as one of the most important the Senate has ever undertaken.
What practical use are these soil surveys? When they find
expression in action they will direct wise land settlement,
provide farmers with information upon which to plan enlightened
farming activity, and guide provincial governments in setting
up forest preserves.
Soil research will be able to determine the kind, yield
and quality of plants that can be produced under various systems
of management on the different types of soil.
Until only recently, farmers, gardeners and foresters learned
about the soil through trial and error, with all its costly
failures and headaches. Today, soil scientists are extracting
facts and providing guidance about the behaviour of soils
under many kinds of practices. Their goal is approached the
hard way, through painstaking fundamental research and observation.
Then comes applied research and demonstration.
The scientist who spends his life studying this dynamic
thing, the soil, comes to have a profound respect for if.
His is purposeful work, directed to the wellbeing of mankind.
But what the survey and the scientist find out to be good
practice must be put into effect by individuals. Personal
conscience is the beginning of conservation, and a forceful
sense of community responsibility will bring about its greatest
advancement.
Expression is given the aims of conservation through organizations
like the adult conservation clubs, the 4—H clubs, school
study groups, and others. Conservation was adopted as the
theme for Canadian Scouting in 1956, and Boy Scouts across
the country promised: "I give my pledge as a Canadian to save
and faithfully to defend from waste the natural resources
of my country ( its soil and minerals, its forests, waters
and wild life." More than nine million children in Canada
and the United States had enrolled in Audubon clubs by 1952.
In these efforts we have the nucleus of a great conservation
movement, for these young people, some of them now grown up,
have learned the need for conservation and some of its methods.
Co—operative effort
It is easier to preach conservation than to achieve it.
Education, research and official planning are not enough.
These must be supplemented and made effective by action programmes.
We cannot conserve our resources effectively if every man
does it in his own way on his own piece of ground in his own
narrow interests. This is a national, a provincial and a community
as well as a personal problem.
As an example of the community nature of conservation, consider
that nature's boundaries are not always land—ownership
boundaries. The imperative unit for soil saving is a valley
that may have a hundred homesteads on its slopes. An effective
contour or terrace system cannot respect property fences.
Your farm is affected by what is done farther up the slope,
and what you do affects land lower down.
Nor are academic boundaries respected by the demands of
nature. Research men of many disciplines need to pool their
discoveries and recommendations: economists, biologists, botanists,
chemists, physicists, agronomists, and many others. What results
as an approved conservation practice is not the product of
any one man or any one discipline, but a blending of all.
An action programme
This account of the problems and causes of soil misuse is
not presented as a chamber of horrors at which to shudder.
It outlines the existing situation so that we may see what
obstacles we must overcome to insure better soil use.
It is time for Canadians to open a soil—saving account.
The virgin land found in Canada up to a century ago was a
very wealthy bank account, but it has been depleted by many
withdrawals.
The conservation work that has been done during the past
twenty—five years looks small against the backlog of
things undone, but it is encouraging. We have been like adolescents
supported by wealthy and indulgent parents, and now we are
beginning to show prudence in approaching the wise handling
of our limited resources.
We must preserve the best that has been attained, change
practices that have proved wasteful and dangerous, and control
new forces or provide for their assimilation.
Public opinion should support all who attempt this vital
work. It might be a good idea for the deans of agriculture
in our universities to gather around a table to sift out the
facts about the needs and methods and response. That would
be a great national service, one that cannot be done with
the same detachment from self interest by any other body of
men. Their pronouncement would be accepted widely, and could
be the guide for national, provincial and community co—operative
efforts.
The challenge is worthy of the best our scientists can give
and of the exercise of the common sense and effort of every
Canadian: to maintain nature's harmony, and to restore it
when necessary.
We all have a stake in success. It is a shorter distance
in time than we think from the splash of a raindrop on an
unprotected hill—top to loss of a farm.
Published by RBC Financial Group. All editions from the RBC
Letter collection are available on our web site at www.rbc.com/responsibility/letter.
Our e-mail address is: rbcletter@rbc.com.
Publié aussi en francais.
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