# Tree Crops/Part 1/Chapter 2

Courtesy U. S. Dept. Agr.
"IS THIS A PERMANENT COUNTRY?"
FIG. 3. Top. No gully, but plucking raindrops have carried away many feet of top soil in this Algerian wheat land. (Photo J. Russel Smith.)-FIG. 4. Center. The most familiar type of erosion. Note the man and note the place-Illinois, the temporarily rich, the supposedly level. (From Univ, of IlI. Circular No. 290.)-FIG. 5. Bottom. A six-foot man stands in the corn beneath the arrow. The worthless stalks by the hat measure the ruin of the hill—typical of forty-five American states. (Photo J. Russell Smith.) ​variable; and 10." (Fig. 1.) Ten tilled crops, and ruin has arrived!
We usually think of Illinois as level land, not subject to destruction by erosion; yet this Illinois bulletin states and shows by this map that "about 5½ millions of acres of land are subject to serious erosion." This is about 9000 square miles, an area larger than Massachusetts.
Even Oklahoma, newest of the new, so recently wrested from the Indian, who did not destroy it, has its million miles ​of gullies and a kingdom of good land ruined and abandoned.
Field wash, especially in America, is the greatest of all
PROFILE OF SOIL AND RECOMMENDATIONS FOR ITS MANAGEMENT
University of Illinois bulletin states that "mangum terrace is best adapted to types of soil slope where sheet washing carries away vast amounts of soil fertility each season."
Oriental Penance. FIG. 7. Top. With great labor Japan reclaims her mountains denuded by past carelessness. Little trees planted by hand on terraces built by hand labor finally renew the forest and hold her mountain side. (Photo Shitaro Kawai. Courtesy U. S. Forest Service.)—FIG. 8. Bottom. By hand labor the Chinese near Nanking carry from a lake bottom back to the mountain side a small fraction of that which need never have left it. (Photo by Prof. Joseph Bailic. Courtesy U. S. Forest Service.) ​resource wastes. It removes the basis of civilization and of life itself. It is far worse than burning a city. A burned city can be rebuilt. A field that is washed away is gone for ages. Hence the Old World saying, "After man the desert."
Can anything be done about it? Yes, something can be done. Therefore, this book is written to persons of imagination who love trees and love their country, and to those who are interested in the problem of saving natural resources—the basis for civilization.
CHAPTER II
THE IDEA
Again I stood on a crest and scanned a hilly landscape. This time I was in Corsica. Across the valley I saw a mountainside clothed in chestnut trees. The trees reached up the mountain to the place where coolness stopped their growth, they extended down the mountain to the place where it was too dry for trees. This chestnut orchard (or forest as one may call it) spread along the mountainside as far as the eye could see. The expanse of broad-topped, fruitful trees was interspersed with a string of villages of stone houses. The villages were connected by a good road that wound horizontally in and out along the projections and coves of the mountainside. These grafted chestnut orchards produced an annual crop of food for men, horses, cows, pigs, sheep, and goats, and a by-crop of wood. Thus for centuries trees had supported the families that lived in the Corsican villages. The mountainside was uneroded, intact, and capable of continuing indefinitely its support for the generations of men.
Why are the hills of West China ruined, while the hills of Corsica are, by comparison, an enduring Eden? The answer is plain. Northern China knows only the soil-destroying agriculture of the plowed hillside. Corsica on the contrary has adapted agriculture to physical conditions; she practices the soil-saving tree-crops type of agriculture.
Photos J. Russell Smith Fig. 12. Top. Olive and fig trees on the hills of Kabylia, foothills of the Atlas Mountains, Algeria. Population twenty-five times as dense as on the same hills where there are no tree crops.—Fig. 13. Center. The pasture year on the two-story Majorca farm. Producing figs, wheat, beans, and clover.—Fig. 14. Bottom. Olive trees in Central Tunis planted (without doubt) by the Romans before A.D. 648 and still bearing—a long-lived property. ​changes earth elements into forms that we can eat and wear, manufacture and burn, or use for building material. This precious soil from which we have our physical being is only a very thin skin upon the earth. Upon the hills and mountains it is appallingly thin. In some places there is no soil at all, and rocks protrude. Sometimes the earth mantle may be only a few inches in depth; rarely does the soil on hill or mountain attain a depth of many feet. Often soil is so shallow that one great rain storm can gash and gully a slope down to bare rock. Where man has removed nature's protecting cover of plants and plant roots, the destroying power of rain is increased a hundredfold, a thousandfold, even at times a millionfold, or perhaps even more than that.
The creation of soil by the weathering of rock is a very, very slow process. Years may have passed in making soil that, if unprotected, may be washed away in an hour. Therefore, today an observer in the Old World might see myriad landscapes once rich with farms where now only poverty-stricken men creep about over the ruined land, while their sheep and goats, scavengers and destroyers, pick the scanty browse that struggles for life in the waste. A handful of men are now living uncomfortably where once there were prosperous villages. Similar examples, even of large areas, can be found in almost any hill country with a long history of occupation by agricultural man.
Syria is an even more deplorable example than China. Back of Antioch, in a land that was once as populous as rural Illinois, there are now only ruin and desolation. The once prosperous Roman farms now consist of wide stretches of bare rock, whence every vestige of soil has been removed by rain. ​Greece, once so great, is shockingly ruined by soil wash. In parts of Europe people even pound stone to get a little bit of loose material in which plant roots can work.
In our own South millions of acres are already ruined, and the same destructive agency has caused ruin and abandonment of land in Ohio, Illinois, Indiana—indeed, in every one of our states. The total of this destruction has been estimated at 16,600 square miles, equal to the cultivated area of England. And yet, as human history goes, we came to America only yesterday.
If we think of ourselves as a race, a nation, a people that is to occupy its country generation after generation, we must change some of our habits or we shall inevitably experience the steadily diminishing possibility of support for man.
FLAT LAND AGRICULTURE GOES TO THE HILLS
How does it happen that the hill lands have been so frightfully destroyed by agriculture? The answer is simple. Man has carried to the hills the agriculture of the flat plain. In hilly places man has planted crops that need the plow; and when a
​plow does its work at an angle instead of on flat lands, we may look for trouble when rain falls.
Whence came this flat land agriculture of grass and grains? The origin of wheat, barley, and many of our important food plants is shrouded in mystery; but we know that our present agriculture is based primarily on cereals that came to us from the unknown past and are a legacy from our ancient ancestress—primitive woman, the world's first agriculturist. Searching for something to fill little stomachs and to hush the hunger cries of her children, primitive woman gleaned the glades about the mouth of her cave. Here she gathered acorns, nuts, beans, berries, roots, and seeds.
Then came the brilliant idea of saving seed and planting it that she might get a better and more dependable food supply. Primitive woman needed a crop in a hurry, and naturally enough she planted the seeds of annuals. Therefore, we of today, tied to this ancient apron string, eat bread from the cereals, all of which are annuals and members of the grass family.
As plants the cereals are weaklings. They must be coddled and weeded. For their reception the ground must be plowed and harrowed, and sometimes it must be cultivated after the crop is planted. This must be done for every harvest. When we produce these crops upon hilly land, the necessary breaking up of the soil prepares the land for ruin—first the plow, then rain, then erosion. Finally the desert.
CAN WE GET ECONOMICS INTO BOTANY?
Must we continue to depend primarily upon the type of agriculture handed to us by primitive woman? It is true that we have improved the old type. Many of the present day grains, grasses, and cereals would scarcely be recognized as belonging to the families that produced them. Present day methods of cultivation but dimly recall the sharpened stick in ​the hand of primitive woman. But we still depend chiefly on her crops.
We are now entering an age of science. At least we are scientific in a few respects. It is time that we made a scientific survey of the plant kingdom—still the source, as always, of a very large proportion of that which is necessary to the existence and comfort of man. We should carefully scrutinize types of agriculture in relation to environment. Agricultural America should scientifically test the plant kingdom in relation to potential human use and do it as carefully and patiently as industrial America has tested cement. We test cement in every possible way, make it of all possible materials, mix all possible combinations, test it by twisting it, pressing it, pulling it; test it thousands of times, hundreds of thousands of times, millions of times, and in a few years our whole physical equipment is made over by reënforced cement made possible by these millions of tests.
THE TREE AN ENGINE OF NATURE—PUT IT TO WORK
Testing applied to the plant kingdom would show that the natural engines of food production for hill lands are not wheat and other grasses, but trees. A single oak tree yields acorns (good carbohydrate food) often by the hundred weight, sometimes by the ton. Some hickory and pecan trees give us nuts by the barrel; the walnut tree yields by the ten bushels. There are bean trees producing good food for cattle, which food would probably make more meat or milk per acre than our present forage crops now make.
These wonders of automatic production are the chance wild trees of nature. They are to be likened to the first wild animal ​that man domesticated and to the first wild grass whose seed was planted. What might not happen if every wild crop-bearing tree was improved to its maximum efficiency? Burbank and others have given us an inkling of what may result from well-planned selection, crossing, or hybridizing.
From Journal of Agricultural An example of variation through artificial selection within the species. Diagram shows an average size of seedlings of Chinese, and Navajo maize planted at different depths. The Navajos, living in a dry country, have selected a strain of corn capable of sprouting from a very great depth and thus having better moisture opportunities. This picture shows how the other corns failed to push out through the sand.
The possibilities, at present quite incalculable, that lie in such work are hinted in one almost unbelievable statement of the great authority. Sargent, who says of the English walnut, which we all know is so good and meaty:
"The nut of the wild tree is small, with a thick hard shell and small kernel, and is scarcely edible; but centuries of cul-
​tivation and, careful selection have produced a number of forms with variously shaped thin shells, which are propagated by grafting and budding." (Silva, Vol. VII, p. 115.)
We now know how to breed plants, In the short space of a few years we can surpass the results of centurics of chance breeding. The plant kingdom has become almost as clay in the hands of the potter. Where we now have one good crop plant, we may some day have five or ten. We need to start in earnest to apply some of our science to producing genius trees—trees that are to other trees as human geniuses are to other men.
Genius trees produced either by chance or design can be propagated a million or ten million times as was done with the one chance navel orange tree.
THE TREE A BETTER CROP PLANT
We need a new profession, that of the botanical engineer, which will utilize the vital forees of plants to create new mechanisms (crop yielding trees) as electrical and mechanical
* ↑ "Five years ago there was not a gully on the place. . . now it is badly cut by gullies . . . all the top soil washed away, leaving nothing but the clay. . . . If not terraced . . . the gullies |will| cut deeper until the rocks are touched or until all the clay soil is gone. . . . Five years ago it could have been saved by spending less than three dollars an acre to have it terraced. To-day it will cost five times as much in addition to getting nothing from it for at least two years."—Oklahoma Extension News, January, 1928. For decades reports of ruin have come out of the hill section of the American cotton belt—thousands of square miles of ruin. Some counties were reported one-third worn out before 1850. Worst of all is the plight of the loess lands east of the Mississippi. This layer of rich, wind-blown soil, half as wide as the State of Mississippi, reaching nearly all the way from the Ohio to the Gulf, is a kind of thin veneer lying on top of coastal plain sands. It is extremly rich and erodes very easily. E. W. Hilgard, the great pioneer writer on soils (Soils, p. 218), says: "The washing away of the surface soil . . . diminished the production of the higher lands, which were then (at the time of the Civil War) commonly 'turned out' and left without cultivation or care of any kind. The crusted surface shed the rain water into the old furrows, and the latter were quickly deepened and widened into gullies—'red washes. . . "As the evil progressed, large areas of uplands were denuded completely of their loam or culture stratum, leaving nothing but bare, arid sand, wholly useless for cultivation; while the valleys were little better, the native vegetation having been destroyed and only hardy weeds finding nourishment on the sandy surface. "In this manner whole sections, and in some portions of the state (Mississippi) whole townships of the best class of uplands, have been transformed into sandy wastes, hardly reclaimable by ordinary means, and wholly changing the industrial conditions of entire counties, whose county-seats even in some instances had to be changed, the old town and site having, by the same destructive agencies, literally 'gone downhill.' "Specific names have been given to the erosional features of this district; a 'break' is the head of a small retrogressive ravine; a 'gulf is a large break with precipitous walls of great depth and breadth, commonly being one hundred or one hundred and fifty deep; a 'gut' is merely a road-cut deepened by storm-wash and the effects of passing travel." In this way we have already destroyed the homelands fit for the sustenance of millions. We need an enlarged definition for treason. Some people should not be allowed to sing "My Country." They are destroying it too rapidly.
* ↑ For references on soil erosion in America, see pages 296-301.
* ↑ In the Mediterranean lands, as in most other parts of the world, there is more rainfall upon the mountains than at sea level.
* ↑ Geikie, in modern times writing of a section of Palestine, gives a similar example: "The ride from Eriha to the Jordan is about five miles over a stony plain, on which there is no vegetation. Year by year the winter rains sweep down the slope and wash away a layer of the wide surface, carrying it to the Jordan, there being little to check them but copses of the Zukkum tree and Apina Christi. Yet seven monasteries once stood on this now desolate tract, three of them still to be identified by their ruins. Until we reach the edge of the Jordan, only the stunted bushes I have mentioned, unworthy of the name of trees, and a few shrubs with dwarfed leaves are to be seen after leaving the moisture of Sultan's Spring. Not a blade of grass softens the dull yellow prospect around." Quoted from Gila River Flood Control, p. 18. Secretary of the Interior, 1919.
* ↑ Von Schierbrand, Wolf. Austria Hungary. Chap. XIV.
* ↑ "Land too poor for crops or grazing, such as old abandoned fields, of which Brazos County (Texas) alone has thousands of acres." H. Ness, Botanist. Texas Experimental Station, Journal of Heredity, 1927, "In many sections of Iowa, Missouri, Nebraska, and other corn belt states water erosion has a tendency to form deep, steep-sided ravines which will sometimes make farming almost impossible in a field as large as twenty or forty acres." Letter, Ivan D. Wood, State Extension Agent, Agricultural Engineering, University of Nebraska, July 19, 1923.
* ↑ National Conservation Congress. See also "Soil Erosion: A National Menace." H. H. Bennett, U. S. Dept. Agr. Circular, No. 33, 1928. This is a document of great value.
* ↑ It is even now probable that the king of all forage crops is a Hawaiian bean tree, the keawe. (Chapter V.)
* ↑ I wish to suggest a little explored line of experimentation, namely girdling, ringing, or otherwise injuring the tree in such a way that it will recover the injury but will, because of it, yield a larger quantity of fruit. This is a regular practice of the Greek growers of a grape that enters the world market tinder the name of currant. It appears that the quantity of fruit a tree bears is in part a matter of habit. I have no idea that most trees bear all the fruit they are physiologically capable of producing. Careful experimentation along this line might be very productive.
* ↑ This creation of new types by plant breeding depends upon three facts—first, the variation of different offspring from the same parents; second, the varying combinations in offspring of the qualities of the parents: and third, the appearance in offspring, especially hybrid offspring, of qualities possessed by neither parent. First, variation of offspring. Look at the children of almost any family you know. This tendency to variation runs deep into both animal and plant life. For example, Texas Agricultural Experiment Station, Bulletin 349, "Variation in certain lint characters in a cotton plant and its progeny" shows that the average length of lint in the individual plants of the progeny of a certain boll (seed pod) varied from 19 millimeters to 285 millimeters, a variation of 50 per cent. This is very suggestive of the way by which through a selection of parents we have changed the cow so marvelously for milk production. The object of selection here is to find desirable strains that produce uniform progenies. Page 15 shows that tree breeding has a more easily attainable objective—namely, one good specimen. Second, varying combinations in offspring of qualities of parents. A hybridization of hazels and filberts (Fig. 20) produced plants ranging from 12 inches to 12 feet in height—suggestive of variations in great degree for each quality a plant can have. Third, the appearance in hybrid offspring of qualities possessed by neither parent. Some of the above-mentioned hazel x filbert hybrids bore