Speeches of HHB, Soil Erosion a Costly Farm Evil
Speeches of Hugh Hammond Bennett
Address by H. H. Bennett, Chief, Soil Conservation Service, Farmers' Week Program, Ohio State University, January 31, 1933.
Soil Erosion a Costly Farm Evil
Land impoverishment and land destruction by excessive erosion, the washing of the soil by uncontrolled rains, have recently come to be recognized as farm and ranch problems of sinister and wide-spread importance. The agricultural authorities of a number of states have declared that this form of wastage is the most serious problem confronting the users of land, pointing to vast areas which have been and continue to be seriously impoverished and to others which have been essentially destroyed by this process that never stops of its own accord. Now we have, also, the evil of low prices; but low prices are subject to change for the better, while soil impoverishment by erosion always grows worse, usually increasingly worse, wherever it is unopposed.
In considering the relation of this problem to the rolling farm lands of the United States, it should be pointed out in the beginning that the evil is much more wide-spread and far more vicious than generally has been supposed. A few years ago, before we knew very much about the enormity of losses due to this malignant process, it was estimated that erosion was washing out of the fields and pastures of this country not less than 1,500,000,000 tons of soil annually.(2) This estimate astounded a good many people. Now, on the basis of measurements at one of the recently established soil erosion experiment stations, it is indicated that in 1930, which was about an average year with respect to regional rainfall, 16,534,800 acres in the rolling Red Plains of Texas and Oklahoma lost 440 million tons of soil. On the 10th of May, 1930, a single rain in the Black Belt of central Texas washed off the rich topsoil from slopes of only 4 per cent at the rate of 23 tons per acre. This one rain, according to a survey made at the time, took a toll of not less than 100 million tons of soil from the sloping part of this famous cotton area. Measurements made at the Blackland Erosion Station indicate that in 1930, 300 million tons of soil were washed out of the 11 million acres comprised in this black prairie belt.
In other words, with the quantitative measurements now being made, it is seen that the preliminary estimate referred to was considerably too small. Now, we are beginning to awaken to the realization that here is a problem whose destructiveness not only greatly exceeds all previous conceptions regarding it, but comes close to exceeding the possibilities of human comprehension.
Erosion a Continuing Process
Erosion steals part of the soil every time it rains hard enough for water to run downhill, taking, successively, thin layers from the surface of the ground, the richest part of the land. It should be made perfectly clear at the outstart that we are discussing man-induced erosion, the excessive washing following (a) the removal of nature's stabilizing cover of trees, shrubs, grasses and decaying vegetable matter, and (b) the weakening of the ground structure by plowing and by excessive trampling of livestock. Probably it would be not far from correct to assert that not one person in this audience has ever seen or ever will see clear rainwater flowing off cultivated slopes in summertime; but most of you undoubtedly have seen clear water running out of woodlands and grass-covered areas at all seasons of the year. The one is discolored with soil picked up from the bare surface of the ground; the other is clear because the ground was protected with the instruments nature employs to prevent rapid scouring away of the earth's surface.
In this connection, please remember that erosion has modified the surface of the earth more than the combined activities of volcanoes, earthquakes, tidal waves, tornadoes and all the excavations of mankind since the beginning of history. That it proceeds slowly, usually taking a think layer at a time, does not in the least alter the significance of the impoverishing effects of the agency, speeded up by man's activities and operating through long periods of time. Unfortunately, this fact of slow procedure does seem to blind the eyes of mankind. The mental processes of the average person never seem to focus sharply upon the accumulative effects of sheet erosion. For some peculiar cause the average man, although seeing the actual performance during every rain, really fails to comprehend its meaning. He views it unconsciously; or, forgetting the principle of mathematics, the progress seems too slow to be impressive. At any rate, few are concerned about the matter until raw, unproductive clay, even bedrock, begins to appear in sloping fields, at which stage it usually is too late to do very much about it. Even now, having forgotten the original condition of the fields, many believe the soil was always yellow or red like the erosion-exposed subsoil, or that the rocks were "heaved up" by frost or invaded the fields by some indefinite process not worth the trouble of looking into.
Erosion an Old Process
Not all men have been so blind to the effects of erosion. The process is an old one. It began in the dim past, probably in the first sloping field cultivated by man. In various parts of the world the evil has been strenuously opposed for many centuries. There are terraces in the Mediterranean basin on which olive trees a thousand years old are still growing. Some of these ancient walled benches were constructed before the time of Christ, built to hold the land in place for continuing agricultural use. In the hinterlands of the Philippine Islands the aborigines were building terraces on steep mountain slopes at the time of the first visit by civilized man. The same thing was true of the ancients of the continent to the south of us, as in parts of Peru. Washington gave up the growing of tobacco, planted clover and practiced crop rotations on his Mount Vernon estate in order to check erosion. You can still see ancient gullies on the lands that once were his. Their proximity to venerable cedars and oaks indicate that they were there in his time.
In 1813 Thomas Jefferson, writing about his farm in Albemarle County, Virginia, said:
"Our country is hilly and we have been in the habit of plowing in straight rows, whether up or down hill, in oblique lines, or however they lead, and our soil was all rapidly running into the rivers. We now plow horizontally following the curvature of the hills and hollows on dead level, however crooked the lines may be. Every furrow thus acts as a reservoir to receive and retain the waters, all of which go to the benefit of the growing plant instead of running off into the streams."
Many of Jefferson's fields are still in good shape, but those of some of the farms adjacent to his estate are terribly gullied. The contrast is enough to suggest that some of his neighbors were not convinced of his assertion that the soil in that part of the country was rapidly running off into the rivers. There still are among us a few who will insist that some of our assertions with respect to erosion are not true. I am inclined to the view that these are men who feel such things should not be true, and, therefore, are not true, as they see it. We shall always have our inborn skeptics, those who call for patience and forbearance, but not much more than that. I am convinced that no normal man, after going out over the slopes of the country and examining the conditions that we shall discuss here, could not but be convinced that erosion is the greatest continuing evil affecting the productivity of our agricultural lands. This is too easy to be checked; I shall not argue the point further.
As stated, we have been living with this evil for a long time; but we have done very little in opposition to it. As a matter of fact, the greater part of the rolling lands of the country is subject in some degree to the impoverishing effects of erosion. Not less than 75 percent of all the land in cultivation, in this country, is rolling land, to the extent, at least, of having slopes in excess of 2 percent.
Erosion Speeds Up
These lands have been used in a way that is conducive to speeded-up erosion. After the topsoil has washed off, and it doesn't take very long to accomplish this on some of our principal types of farm land, the exposed subsoil in most places washes faster than the soil. Already we have permitted essential destruction of at least 21 million acres of formerly cultivated land by gullying and by the covering of low-lying areas with infertile wash from above. We have been able to put our fingers on this much destroyed land. But this is the least of the evil. A far greater area has been severely impoverished by sheet washing, that process which planes off a thin layer of soil, more or less equally over entire fields, with every heavy rainfall. What I have seen during years of study leads me to the belief that not less than 125 million acres of the land now in cultivation in this country has lost all or the greater part of its more productive topsoil. It is my belief, also, that not less than 34 million acres of formerly cropped land have been destroyed by the more spectacular type of washing-gullying and deep sheet washing.
Some of us have fallen into the habit of thinking that where there are no gullies there is no erosion. This is an error that we are trying to correct. Already we have found that by continually explaining the meaning of sheet erosion, by writing about it year in and year out, and pointing it out to those who will look, a large number of farmers and others are taking more interest in the problem of erosion and its control. Some of those who had seen sheet erosion in the full blossom of its insidious operation, without duly appreciating its significance, recently have been awakened to its really deadly impoverishing effects, not only in this country but on the rubber and tea plantations of the east, the pineapple plantations of Hawaii and up and down the continent of Africa.
The United States the Most Wasteful Nation
When I speak of many farmers having failed to see these things, I do not want to be understood as meaning that only farmers have been guilty. Most of us have been blind and soundly asleep with respect to the real meaning of erosion. Some of our classical volumes have described practically every process relating to the agricultural use of land, save this one. Some of them do not so much as mention the problem, which more than any other single agency having to do with man's activities, or combination of such agencies, is impoverishing the agricultural lands of this country. We have gravely pointed fingers of warning in the direction of China as a country whose land practices should be anathema to the farmers of our own youthful country. This would seem amusing, if it were not so tragic. The probability is that of all the countries of the world, we of the United States have been most wasteful of our land resources. I am familiar with the greater part of the agricultural area of this continent and most of that over the northern half of South America. Within that great area not one country has even remotely approximated the conditions with respect to impoverishing erosion that we have in great abundance here in the United States. This is due partly to the peculiar characteristics of our soils and rainfall and partly to our farm practices. It is also due in part to our stupendous ignorance with respect to the gouging effects of rainwater running across unprotected slopes. We are 75 to a hundred years behind with our studies relating to these processes and to methods of controlling them. We have diligently studied almost every other agricultural subject but this one, the one which should have been studied first. Vast areas of land have been destroyed in other countries, to be sure, but the destroying process took thousands of years. The headway we have made in this direction, which I am going to discuss more specifically in a moment, has largely been achieved within the brief period of less than two centuries, most of it within the past 30 to 50 years.
Some Examples of Land Impairment and Land Destruction
Piedmont Region: Our surveys indicate that from 4 to 18 inches of soil and subsoil have been washed from 65 to 70 percent of the cultivated (present and past) part of the 50,000,000 acres comprised in the Piedmont region, which extends from New York City, down along the east side of the Appalachian Mountains, into east-central Alabama. Thousands of former fields have been cut through with gullies, down to the bedrock from which the regional soils have been derived throughout eons of rock decay and of the soil building that goes on under nature's stabilizers of vegetation, chiefly forests. The desecration has been just as bad over parts of the northern extension of this old agricultural area, as in central New Jersey, as it has been in the middle and southern parts.
Twenty-two years ago a soil survey made by the Federal Department of Agriculture, cooperating with the South Carolina Department of Agriculture, mapped in one county 90 thousand acres of formerly tilled upland under the designation Rough Gullied Land. Except for occasional patches between the gullies, this area was appraised as being too rough for cultivation. It represented destroyed land, largely valueless for anything but trees and scant grazing.
At the same time, 46 thousand acres of stream-bottom, once the most productive soil of the entire state, were classed as Meadow, or land covered with sand and mud washed out of the cultivated hills, and thus made subject to increased overflows due to the choking of channelways with the debris of erosion. In addition to the ruining of those 126 thousand acres of former good crop land, every sloping field of the county was suffering from sheet washing.
I had supervision of this soil survey in 1911. Last September I went back into the county to see what had happened during the intervening years. My investigations led to the opinion that a new survey would show that the area of gullied land now amounts to 125 thousand acres, and that many additional strips of rich alluvial soil have been ruined.
Roads Washed Away: I undertook to drive over three different highways from the county seat which formerly I had traveled comfortably with horse and buggy. It was impossible to go but a short distance along any of these. They had grown into canyons, trees had sprung up in them; they were abandoned. Finally, by a roadway that wound between gully heads, I came to an old farmstead, where the residence, the "Big House," once a magnificent structure of the pre-Civil War type, with great formal columns, was tumbling to pieces. The beautiful columns lay rotting on the ground, the roof had fallen in, the porch had collapsed, from two to three feet of soil had washed from about the foundation stones. This farm comprised 1,004 acres, all formerly cultivated. No longer is any of it cultivated. I found not so much as an acre in one place that I considered worth cultivating. The soil had washed away everywhere, in most places the subsoil was gone. Soft rotten rock, even hard bedrock, was exposed in countless places. The plantation graveyard stood on a hill less than a quarter of a mile from the farm residence. It took me more than half an hour to reach it, so deep and fingering were the intervening gullies. These ravines extended to the very edge of the burial place.
No one lives on the land. From the higher points, all the surrounding country was observed to be much the same: Destroyed land, worn-out and abandoned as far as the eye could reach. Silence pervaded the landscape, desolation, irretrievable ruin. Man had laid bare the bosom of the earth to the wrath of the elements. Nature had wreaked vengeance upon this once beautiful countryside; and yet, the same agency had set to work to rebuild what it had torn down. Pine trees had sprung up in every direction. Some of the land was too poor for trees, but much of it was covered with volunteer forests. Thus, the first step toward rejuvenation of the worn-out land was well under way. Unfortunately, the rehabilitation in all probability will require more than a thousand years.
Land Impairment and Destruction in Georgia: Crossing the Tugaloo River into Georgia, I soon came to a high Piedmont county where one of the state soil men was completing a soil survey. Here the conditions were even worse than in the Carolina area referred to. More than a hundred thousand acres of formerly tilled land had been essentially destroyed and abandoned in this one county, and an additional 150 thousand acres were so eroded that practically every field included gullies which could not be cultivated at all. The farmers still clinging to these impoverished fields can not use them much longer, not as crop land at any rate. Operating as subsoil farmers, there is little chance for the making of a comfortable living on these poor lands, even when prices are good. These fields will be laid aside within another decade or so. They will grow up to trees, but they can not be farmed again, not even by the grandchildren of those now living on them. These farmers must move higher up on the smoother ridge tops, or lower down into the creek bottoms, else quit farming in that locality.
From this severely eroded Piedmont county, I drove down into the coastal plain section of southwestern Georgia. I was there in 1913, inspecting a county soil survey. At that time, twenty years previously, we mapped in this county 37 thousand acres of the best type of land in all of south Georgia as Rough Gullied Land, largely without any possibility of cultivation. At the same time, 33 thousand acres of formerly tilled land were mapped in the same area as worthless for crop production, owing to the impoverishing effects of sheet erosion, accompanied by considerable gullying. Also, nine thousand acres of once good bottom land were mapped as worthless Meadow.
I found on this second trip that the gullies had not stopped with their chiseling away of the fine agricultural lands. They had grown longer, deeper, and wider; they had branched out, forming new canyons. A roadway which I had traveled previously had been moved; it must be moved again. But it can be moved but once more, since yawning ravines are approaching from the opposite direction.
Some of the gullies are 200 feet deep. I talked to a 73-year old farmer who once went to school in a schoolhouse that stood in the center of "Providence Cave." Providence Cave is one of these enormous gullies, probably the deepest man-made gully of the Western Hemisphere. If it were there today it would be suspended 200 feet above the bottom of the canyon. Along with the barn from whose roof dripped the rainwater that started this gully, the schoolhouse has fallen into the chasm, as well as a tenant house and a graveyard with fifty graves. Thus, buildings and the remains of human beings have intermingled with the debris from 50 thousand acres of splendid farm land, as waste material marching down to the Gulf of Mexico.
Engineering works like those employed in the building of the Panama Canal would be required to restore these chasms to a condition of economic value. They will not be restored, of course; this can not be done upon any practical basis. The gullies should never have been permitted to develop. Every one of them could have been checked in the beginning; but it is too late now. It is not too late, however, to prevent the formation of others. One farmer with whom I talked built a diversion ditch around the head of one of those gullies in its infancy, twelve years ago. The rainwater was directed off to the sides, into the nearest streamways. In the meantime, this particular gully has made no appreciable headway.
Soil Washing in Alabama: The road I followed then led me to central Alabama, into a region where, by actual survey, something over 500 thousand acres of formerly tilled land, much of it the best in the coastal plain section of that state, has been shown to have been abandoned because of excessive erosion. Much of this should never have been cleared of its original growth of hardwoods and pine, because of its steepness; but many thousands of acres of gently sloping land, also, have been cut to pieces. Large sections that formerly supported numerous farmsteads are now a wilderness, covered with second-growth pine, through which not a single roadway can be traveled.
While in the state, I said something to a prominent soil specialist about collecting a sample of virgin soil from the rolling black prairie region, extending from central Alabama across into Mississippi. He replied (as I thought he would) that although he had covered every acre of this great stretch of country, if one should ask him to get such a sample he would not know where to find it. The soil had washed off, and in many places the subsoil too, on down to the unproductive Selma chalk which gave rise to the famous black land of this one-time rich cotton producing section. The bottom lands of the Black Belt, and the flats adjoining, are still productive; but a large part of the country is neither bottom land nor flat land. It is rolling upland, deeply eroded. Much of it has been turned to Johnson and Dallas grass, both of which get along fairly well in the former fields. The land is being extensively used for hay and for grazing. This is one instance which strikes me as constituting as nearly correct land utilization as anything I have seen anywhere, even though the use that preceded the present system was quite the opposite of good land usage. In time, under this treatment, these lands will make considerable recuperation.
The Black Belt of Central Texas: This region, whose fame as a cotton-producing area is known to the ends of the world, once was a real black belt of highly productive black clay, rich in lime, humus and plant nutrients. Vast changes have come over the region since it was broken out of the prairie sod some 30 to 50 years ago. It is no longer an unbroken black belt, but a mixed black and white belt with countless areas scoured off to the underlying white chalk or marl. Many fields that once produced from three-quarters to a bale of cotton per acre now requires 10 acres to make a bale of cotton. In dry years I have gone through fields which would require 40 acres to produce a bale, according to the estimates of those farming it, as well as my own. If erosion is permitted to proceed at the present rate the proper name for the "Black Belt" eventually will come to be the "White Belt." A single rain in May, 1930, washed 23 tons of soil per acre from a gentle slope of this black soil, which was planted to cotton. The soil was collected in a tank at the foot of the slope and weighed. A few more such rains will carry the surface of this field, and thousands of others like it, down into the white substratum material.
Erosion in the Red Plains Region: A large part of the 36 million acres of predominantly red sandy lands extending from western Oklahoma far down into Texas has undergone terrific erosion during the past generation, with hundreds of fields ruined by gullying and many more depleted by sheet washing. Two years ago the Agricultural College of Oklahoma made an erosion survey of that state. Of approximately 16 million acres in cultivation, 13 million acres were found to be suffering seriously from erosion. Of this, nearly 6 million acres had reached the stage of gullying, and almost a million and a half acres of formerly tilled land had been abandoned because of erosion. It seems not so long since hundreds of homesteaders, at the crack of muskets fired by United States troops, were rushing into the Cherokee Strip of Oklahoma for the purpose of locating free farmsteads. What has happened in this region since then is tragic beyond belief.
Effects in the Corn Belt: A tremendous amount of land has been severely impoverished in the rolling counties of northern Missouri, southern Iowa, eastern Kansas and southeastern Nebraska, and many farms have been abandoned as the result. According to available measurements, soil is being lost in this region, from the extensive type of land known as the Shelby loam, more rapidly than anywhere else in the country. In 1931, at the erosion experiment station near Bethany, Missouri, 106 tons of soil were lost per acre from an 8-percent slope cultivated to corn, where the field was 125 feet across, and 85 tons where the field was 73 feet across. Approximately 30 percent of the rainfall ran off with this soil. At this rate of washing only 3 to 12 years would be required to remove 7 inches of soil. On slopes of this gradient the soil is just 7 inches deep, and below it is stiff clay subsoil which produces corn at the rate of about 17 bushels an acre. The original soil, as broken out of the prairie grasses, produced from 50 to 75 bushels of corn to the acre.
Erosion in Other Areas: Probably there has been proportionately more land destruction in the area of rich limestone soils within the Ohio Valley, the Great Valley of East Tennessee, the limestone highlands of Kentucky and Tennessee and the once fertile valleys of northwest Georgia and northern Alabama than in any other part of the country. We have made very general surveys only in those regions, and consequently have only rough estimates of the damage. Recently I found on practically every slope cultivated long enough for the stumps to have decayed that either clay subsoil or gullies are in evidence all the way from the vicinity of Birmingham, Alabama, nearly to Bristol, Tennessee. In one section twelve miles long, it was estimated that 85 percent of all the cultivated land as far as one could see to east and west had been ruined by gullying. Part of the remainder was still covered with the fine hardwoods that once occupied all of this splendid area. Much of it originally was of the best type of upland to be found anywhere in the eastern part of the nation, the Decatur silt loam. Thoughout a distance of 300 miles, largely limestone country and originally highly productive, not a single instance was observed where anything had been done to check the wholesale devastation by gullying and sheet washing, aside from the throwing of a bit of brush into an occasional gully.
Erosion Going On Over Most of the Country: The evil effects of this scourge are absent from but few parts of the country. There is very little soil washing, for example, in western Washington State, where the rains fall slowly and the ground is highly absorptive. Also, there is but little on much flat land of the central states, although probably more than is commonly supposed. In this connection, the records of erosion studies at Spur, in western Texas, might be recalled. Here it has been shown that clay loam soil having only a 2 percent slope is losing soil under cotton production at the rate of 12.7 tons per acre, while on perfectly level land the loss is running at the rate of 4.2 tons per acre.
The Situation in Ohio: We have no measurements as yet of the rates of erosion for the state of Ohio, but we know that it is proceeding all too rapidly, especially in the hill country of the southeastern section. In the fall of 1931, a number of specialists in forestry, crops, soils and agricultural engineering were studying erosion on the soils of southeastern Ohio. With the aid of a soil map, it was estimated that in one county approximately 200 thousand acres of formerly tilled land have gone out of cultivation, except in an occasionally patchy way. About half of this is being used more or less regularly for pasture; the other half is not being used for any purpose aside for patches here and there which occasionally are plowed or temporarily used for grazing. The fences are falling down and abandoned houses are scattered about the country. Poverty grass, golden rod and dewberry vines cover much of the land.
Checking the original conditions as revealed in remaining patches of timber, where the land had never been cultivated, it was possible to determine the depth of the original soil. By comparison, it was learned that most of the abandoned land had lost all or a considerable part of its mellow humus-charged surface layer, which is the most productive part of the land everywhere, and the farmer's principal capital. Not only had this washed off over a large part of these impoverished areas, but the subsoil also had been removed in many places on down to a mixture of yellow silty clay and rotten shale, so acid, unproductive and erosive that poverty grass and golden rod were not succeeding any too well on it. At one place, where 1,200 acres could be seen in a single block, an appraisal was made of the apparent possibilities. The forester looked upon it as a pretty tough proposition from the standpoint of growing hardwoods. He said that pine trees could be made to grow by planting, but he was skeptical as to the probability of the average farmer accomplishing very much in this direction. The soil-crop man, who was quite familiar with such conditions, stated that while a fair stand of grass could be established at a cost of $10 an acre for lime and superphosphate, he was of the opinion that few farmers would be inclined to spend that much, or even a fraction of that sum, on land which had reached such a low state of productivity. The agricultural engineer asserted that it would be entirely unprofitable to undertake reclamation of such land with any engineering methods with which he was familiar. The unanimous verdict was that such essentially destroyed land had best be left to the vicissitudes of tax delinquency and whatever beneficent work nature might accomplish unassisted.
Recently, a tract of land has been acquired near Zanesville for carrying on experiments to determine the most practical methods for conserving the soil which still remains on the slopes of southeastern Ohio. A soil survey of the farm was recently completed, and also an erosion survey. These show good land in the timer and some, also, over the cultivated part of the farm, where the slopes are not excessively steep and where farming has not been carried on very long. Unfortunately, however, they show entirely too much land which not only has lost its soil but its subsoil, down to, or nearly to, shale rock.
Recently I presented before a meeting of the Association of American Geographers two ears of corn taken from an eroded field on this farm. One was the largest ear I could find, the other the smallest. When these were held up before the audience, one of the geographers complained that he couldn't see the little ear. I think his complaint was not based on any defection of his eyesight. That corn crop just wasn't worth growing. The soil where it was grown is poor, sour, droughty, and hard to plow. The gross income from an acre of it would have amounted to only about $3.50, at a price of fifty cents per bushel.
The situation was entirely different, however, over on another part of the farm, where the topsoil still remained. In that case a good crop of corn was produced last year, the yield amounting to about 40 bushels an acre. That would have brought $20 an acre, had the price been fifty cents, which it wasn't, by a long ways. At any rate, both soils originally were the same; one is still good land, as land goes in that section, while the other is precisely the opposite.
One of my good Ohio friends who knows the state from end to end told me when I was out at Zanesville recently that the worst erosion in the state is down in another county to the south of Zanesville. I told him I would like to see it. His reply was that he didn't know just how he could show it to me, since so much of the land had been abandoned that there really weren't any negotiable roads through it.
These Ohio boys have been telling me that the eroded lands of the state are down in the eastern and southern sections. I know these localities fairly well, and have seen throughout them many thousands of acres of once good shale soil and high-powered limestone soil that have been ruined by sheet washing and gullying. Numerous slopes in the Ohio Valley once occupied by highly productive limestone soil have been gullied right down to bedrock. A few years ago I came across a farmer who was plowing a sloping field of such soil, down near the Ohio River. Gullies had cut down to hard limestone in many places leaving the field in the shape of a series of blocks, each separated by a streak of limestone. The farmer was having a lively time of it lifting his plow across the washes. Asked if that wasn't a pretty rough field for plowing, he replied: "You are right about that, brother, but the point is this soil is so good I figure it's worth the trouble." It was a case of using the land to the last grain of soil. What a field that must have been in its prime, and what a pity something was not done to conserve it. I am sure it could have been saved, but it is gone, by now the last grain of it probably.
But there is at least some erosion in other parts of Ohio, not on the flat lands but on the rolling areas. I say this because I have seen it. However, had I not seen it there would be reason for suspicion, because recently I have been getting some letters from farmers scattered around over those areas who insist that they have a lot of washing on their farms and want to know what to do about it.
Cost of Erosion
The potential value of the plant food contained in the soil washed out of the fields of America every year, based on the average chemical analysis of the soils of the country and the cheapest form of commercial fertilizers, amounts to about $2,000,000,000. The indications are that in normal times the actual annual cost caused by erosion is in the neighborhood of $400,000,000.
The debit side of the process does not end with the direct impoverishment and destruction of upland fields, and the consequent increased cost of cultivating, fertilizing, liming and the growing of soil-improving crops on stiff erosion-exposed clay. Much of the material washed out of fields and pastures is deposited over lower slopes and productive bottom lands where it usually is not needed because of the original productivity of these lands. Unfortunately, much of this overwash is poorer than the soil it covers, as in the instance of relatively unproductive sand and gravel laid down over rich loam or clay; or of poor, raw, humus-deficient clay washed out of gullies down over good loam, mellowed with humus. Moreover, with stream channels choked, overflows become more frequent, causing the abandonment of land that once was high-grade farm land. Reservoirs are filled with mud, as well as irrigation and drainage ditches, harbors and fish ponds. Highways are covered and culverts are filled with outwash material; even the streets of some cities and towns have to be cleared of the products of erosion following spring rains, i.e., they have to be de-mudded.
Again, it is not in fields alone that erosion piles up its toll of expense. The shoulders of highways are cut away, the faces of road embankments are undercut and gullied, and roadside ditches are converted into troublesome ravines. Thousands of baffles, concrete and wooden dams, stone and earthen dams, and even grass dams have been built in roadside ditches to prevent their enlargement; honeysuckle, Bermuda grass, wheat, rose bushes, and shrubs have been planted along many miles of highway shoulders and cut-banks to stabilize them against destructive washing. Earthen dams, railway cuts, lawns and even golf courses call for special treatment. So do farm buildings, occasionally, and vast areas of grazing land. I am familiar with one flood along the Rio Grande that destroyed two towns and numerous farm buildings, washed out railway bridges and piled up so much sand over long stretches of rail line that more than a million dollars were spent to repair this latter item alone. Another flood, following a fire on a nearby watershed, spread so much sand in the orange groves of a comparatively small section in southern California that it cost the owners $100,000 to haul out the sand. The Harding Reservoir of California was completely filled with stones, sand and mud by one flood issuing from a burned-over area in the nearby mountains. Bell's Mill Pond, near Gainesville, Georgia, was a popular bathing resort two years ago. Today, if one should dive into that pond, it would be sand, not water, the diver would splash into. The reservoir is entirely filled with sand, but the diving tower is still there.
In one of the best farm counties of the Mississippi Delta Region a survey has shown that 180,000 acres of rich alluvial land have been damaged to the extent of about $10 per acre, or a total of $1,800,000, by deposition of infertile sand in small mounds locally known as "sand blows." Here is a case which conflicts with the ancient saying to the effect that one man's loss is another's gain. It also conflicts with the notion that all floods enrich the valleys over which they flow, by reason of the rich silt laid down as sediments. That does happen at times, but not always by any manner of means.
National Program of Soil Conservation
Realizing the enormous cost of soil erosion, and the fact that with tens of thousands of hard-working farmers, operating on severely eroded lands, it is impossible to make a real living even when prices are good, Congress, four years ago, provided funds for getting under way a national program of soil conservation. The primary purpose of this program is to devise practical measures for saving the soil yet remaining on the sloping farm land of the country, and to determine the best use for those lands which have been largely stripped of their productive surface soil. Eleven erosion experiment stations have been established in as many major soil and climatic regions, where erosion is known to be a very grave problem.
For the first time in history this problem is being studied in a really scientific manner. The information which we should have had 50 or 75 years ago is just now being acquired. We are finding out how rapidly soil is being lost from different soils, occupying different slopes, devoted to various crops, cultivated in different ways, and the manner by which these losses occur. We are learning, also, how the losses can be reduced or controlled. Every promising practical method is being tried out as rapidly as it can be put under experimentation. Already we have learned that we really have known very little about erosion processes. But we are making headway, we are getting our hands on some of the fundamental facts that long have been acutely needed as a basis for correct procedure. We have learned, also, that the job is one of immense proportions. The difficulties are legion. Obviously, we ere going to need all the help we can get. If any of you have any suggestions to give us, any worth while results based on actual farm experience, please tell us about them, remembering that if this is to be a permanent nation we must save this most indispensable of all our God-given assets-the soil, from which comes our food and raiment. If we fail in this, remember that much sooner than we have expected this will be a nation of subsoil farmers. For lack of foresight and willingness to look to the future, our children will condemn us, as already I have heard the children condemn the practices of their forebears in a number of American communities where erosion has turned back the hands of progress by laying waste the very productive substance of the country.
We can not afford to admit the possibility of failure in this fight. The penalty is too inconceivably severe. We must, in this combat, insist, as some one has said, that "There is no failure except ceasing to try."
The Northwestern Appalachian Erosion Station
In cooperation with the agricultural specialists of the State of Ohio, the Department of Agriculture is getting under way the Northwestern Appalachian Erosion Experiment Station, located some eight miles west of Zanesville. Here we shall undertake to fight out this matter of determining what are the most practical methods, or combination of methods, for controlling soil erosion, as it affects the great areas of Muskingum silt loam, stretching across southeastern Ohio into Kentucky, Pennsylvania, and West Virginia. Using this station as a base, it is planned later on to go out on other important soils, for the purpose of working out on them, also, the cheapest and most effective practices for keeping the soil in the fields and out of the valleys.
We expect you to visit this station as soon as it gets to going, and to keep on visiting it. Not only that, we want you to come prepared to help us. Criticize what we are doing all you please, so long as you do it in a constructive way. Bring us your own ideas; bring your neighbors and their ideas. If you learn anything from our efforts, then make of yourself an apostle and spread the gospel throughout the community. Never forget that we can not afford not to do these things. Some of you doubtless have seen old worn-out farmsteads where a man might spend a lifetime without bettering himself or his farm. We are creating farms of that kind too rapidly in this country, far more rapidly than you have supposed. No farmer, community, county, state or nation can afford to put up with any such neglect and waste; certainly not, without moving heaven and earth to put a stop to it.
No Threat of a Land Shortage
It is not to be understood from the dismal things I have said that we are on the verge of a land shortage in this country. No, we have too much land for that. We are not likely any time soon to run short of an adequate supply of food. Even erosion-impoverished land will produce something, at least that will which is not too gullied to be plowed. In the aggregate it will produce a great deal. The point to be stressed is that we are likely to run into a shortage of good land much sooner than most people think, even our technologists, or many of them at any rate. Good American soil, capable of producing real crops, rather than the pitifully pauperized yields derived from poverty-stricken soil, is none too plentiful now. Once we looked upon our vast agricultural domain as an empire of inexhaustible land, just as we felt about our wildernesses of forest. I remember when log-rollings were on a part with corn-husking as a means of local entertainment. Those logs were rolled into great piles, not to be hauled off to sawmills, but to be burned, in order to get the trees out of the way.
The yields of our crops are not increasing. Notwithstanding the betterment of varieties and cultural methods, the improvement and increased use of farm machinery, the increased use of fertilizers and soil improving crops, and the far-reaching assistance of educational, research and extension services, the acreage yield of corn has dropped from 27.04 bushels for the 10-year period 1871-80 to 26.13 bushels for the 10-year period 1921-30. The yield should have gone up, not down, since the crop has not spread out in any large measure to the dry lands of the country, nor has it suffered seriously from wide-spread insect and plant disease scourges. In 1869 we spent 6 millions of dollars for fertilizers; in 1929 we spent 233 millions. Much of this was applied to corn.
The average yield of cotton for the periods given dropped from 186.4 pounds of lint per acre to 153 pounds per acre. In numerous localities the yields of both cotton and corn have declined much more than these national averages. In many sections where corn once was grown in surplus amounts, numerous fields have been abandoned and large quantities of the grain are shipped in.
Need for Better Farming on Better Land
Never before in the history of the country has there been greater need for better farming on better land. By this is meant not only the practice of those improved methods of farming that pertain to the building up of the fertility of the soil with humus-supplying legumes and other soil-improving crops, but to better protection of the land against wastage by rainwash, thus to close as effectively as possible the open bung-hole through which pours almost unnoticed soil and soil fertility at a rate which exceeds many times the rate of soil depletion of the crops removed. As yet, not enough data have been accumulated to state precisely how much soil is wasted annually from our farm and grazing lands, but we are on the track of this information. The actual losses may amount to ten times as much as the enormous estimate to which I have referred; we are not yet prepared to say. But we are prepared to say that we can not continue as we have in the past without becoming dangerously unbalanced with respect to the proportion of poor land to good land.
Some soils are inherently poor. They were poor the day there were stripped of their forest cover or prairie sod. There was not much hope on these lands to begin with. Other soils that ranged from fair to excellent have been reduced to the condition of poor land by erosion, and the process is speeding up. More and more we must strive for the maintenance of the virgin fertility of our farm land, or that part of it remaining as topsoil. We can never really have the good land utilization we hear discussed so much nowadays until we learn to give better protection to our sloping fields.
Depth of Topsoil
When we come to examine the depth of the topsoil over the uplands of the nation it is found that this layer is much shallower than most people think. The average depth of the topsoil of these uplands, including both the dark-colored surface layer and the layer immediately beneath is not over nine inches. Many of our most important types of farm land range from only about 3-1/2 to 6 or 7 inches in depth of true surface soil. From some of those types we are losing this invaluable layer with 8 to 40 or 50 years of cultivation, depending on the kind of soil, the slope, the character of rainfall, the type of farming, and the care taken of the land. When this important layer is gone the operator becomes a subsoil farmer. It is entirely impractical to undertake to haul soil back to the upper slopes from which it has washed, even of that which is temporarily deposited along the lower slopes. Of course, that which goes down into the beds of rivers, into the oceans and over the coastal marshes has passed beyond the possibility of usefulness. When the soil is gone it can not be restored by ordinary building processes, not within the span of the average man's life. By growing the soil-improving crops, by liming and fertilizing and intensive cultivation we can increase the productivity of some eroded land, to be sure; but we can not replace precisely what nature put there-the mellow, loam-like soil that took centuries in the building. By terracing, strip cropping, plowing humus into the soil and practicing good rotations it is practical to slow down the wastage by erosion to a very great degree, especially where our operations are confined to slopes that are not too steep. The steeper slopes should be kept in grass or trees, and those that are suitable for plowing should be protected, just as the sheep-herder watches over his flock while among wolves and cougars.
Some Results From the Erosion Stations
It will not be possible to give here more than a few summarization's with reference to the results that have been obtained at the erosion experiment stations recently established throughout the country, and, also, through the medium of surveys.
Erosion Losses: The rate of soil washing is enormously affected by steepness of slope, type of soil, intensity of rainfall, the crops grown and cultural practice. In less degree, length of slope affects the rate of soil removal.
Not only does erosion-exposed clay absorb less water than the mellow loam that originally covered it, but that which is absorbed is either lost more rapidly in dry weather or is much more difficult of extraction by the roots of plants.
The supply of available plant food is markedly reduced by the removal of the surface soil, as well as the population of beneficial microorganisms. The humus supply is usually exhausted by this radical change.
Raw, stiff clay exposed by continuing washing is more difficult to plow, and consequently more costly. These costs are pyramided with damage to lower lands by overwash of the products of erosion, by increased floods, by the filling of canals, ditches, rivers, reservoirs and culverts. They are further added to by the undercutting of expensive highways, by the washing of highway and railway embankments and by damage to earthen dams.
Erosion Control: Vegetation of all kinds slows down erosion. The thicker the cover, the more effective it is. The loss from corn grown on an 8 percent slope in north Missouri, in 1931, amounted to 106 tons of soil per acre and 28 percent of the rainfall; the corresponding losses from alfalfa grown alongside were only two-fifths of a ton of soil and 2-1/5 percent of the rainfall. On the principal wheat soil of western Kansas, clean-tilled Kafir has lost, as an annual average for the past three years, 14-2/5 tons of soil per acre and a fifth of the rainfall, as against only four-thousandths of a ton of soil and 46-thousandths of the precipitation from the native plains grass. In other words, grass growing under precisely the same conditions was 3,600 times as effective as Kafir corn in holding back soil and 434 times more restrictive with respect to retention of the rainfall.
Ground covers (mulches) of wheat straw, forest litter and other waste materials of this nature exert a powerful influence toward diminution of erosion.
Vegetable matter incorporated with the soil usually largely reduces erosion, although there appears to be limitations with respect to this practice: Points of saturation, beyond which the treatment is characterized by diminishing returns, even reversal of the benefits. Wheat straw, after rotting, is a promising source of material for such use, at least in some localities where the straw is usually burned.
In every measurement made, crop rotations have cut down the losses of soil and water. At the north-Missouri station the losses from corn grown in rotation with wheat and clover were 148 percent and of water 19 percent less than where the crop was grown continuously under the same conditions of soil and rainfall.
Strip-cropping, i.e., the growing of thick crops such as grass, sorghum, and alfalfa in strips along the contours, between clean-tilled crops, has markedly reduced erosion, both by wind and water. At the Blackland Station in central Texas, no soil was lost, and but very little of the rainfall, for a period of 20 months.
The running of crop rows across the slopes, at approximately the same level, has greatly diminished the washing, as compared with plowing up and down the slopes.
Scarification of wheat land in the Great Plains region and in the Palouse wheat bolt of Washington, Oregon and Idaho, with a machine which rapidly and cheaply digs 10,000 holes to the acre, has largely reduced erosion. The holes take care of about 5 gallons of rainwater each. This implement is now being developed for use with row crops.
Terraces have largely reduced erosion. In the less humid regions level terraces have held all the rainwater on the land, greatly increasing crop yields and reducing erosion.
Summer and winter cover crops have largely minimized the wastage, and, along with good crop rotations, have made terraces more effective.
Gully Control: Small gullies and shallow marshes are being checked and reclaimed by the use of inexpensive grass dams made of waste fertilizer and grain sacks filled with soil and sod of various grasses.
Excellent results with gully control have been obtained by planting willows, honeysuckle and other types of vegetation in the bottoms of ravines, and, also, by plowing down the sides of gullies and planting them to black locust, buckbrush and grass.
Cheap brush dams, dams made of waste wire, log dams and rock dams are being effectively used in the control of gullies.
Concentration of Water: In west Texas, waste water from a 1,200-acre watershed was concentrated during the past year and distributed over 120 acres of lower-lying crop land with excellent results. In June the waste water from a 1-3/4 inch rainfall was spread out over this area by means of a cheaply constructed system of embankments (terraces) with the result that the field soaked up the equivalent of a 7-inch slow rain. The yields were enormously increased and apparently enough water absorbed to insure a good crop in 1933.
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