Conservation Reader Part 7

While it is raining, let us fill a bottle from some muddy stream and allow it to stand until the water settles. In the bottom will then appear a layer of fine mud, or _silt_ as it is usually called. How much soil do you suppose the rivulets washed from my garden and from yours during the last severe storm? How much do you suppose all the rivulets which make up the rivers of your state washed from all the gardens and fields during the same storm? Make a guess and then multiply your answer by the number of storms in one year and that by fifty years, and you will get a quant.i.ty greater than you would believe possible.

This is the way Nature takes her toll for our carelessness. So quietly does she do it that often the farmer does not have any idea of what is happening. She is like a thief that comes and steals his goods while he is sleeping.

[Ill.u.s.tration: _Bailey Willis_ The soil on the hillsides of China is being washed away because of the thoughtlessness of the people.]

When the farmer finally awakes and begins to wonder why his crops grow smaller each year, he has already lost the cream of his soil. He must at once stop plowing the steep hillsides and leaving the ground bare for the winter rains to wash it away. To save the slopes he can either terrace them or he can sow gra.s.s or clover, which will form a sod and hold the soil. If the farmer can get peas, beans, alfalfa, or clover to grow upon his wasted lands, they will make it fertile again, for these plants have the wonderful power of taking nitrogen from the air and storing it in the soil.

[Ill.u.s.tration: _American Forestry a.s.sociation_ The farmer who owns this land will soon be made poor because of his carelessness in destroying the covering of the soil.]

More earth has been washed from the hillsides of our country during the last fifty years than during thousands of years before white people came. The farm lands have been injured, the bays have been made shallower, and many river channels have been so filled up that it is more difficult to navigate them now than it was in the early days.

The farmer, the stockman, the lumberman, and the miner has each been selfishly doing his share in the destruction of the soil. Each one has thought only of how he could make the most money in the shortest time.

It has not occurred to them that they are making it difficult for their children and grandchildren to live.

In the Southern states thousands of acres are being gullied by the rains, and the soil destroyed. The floods of spring have become worse in late years, because of the destruction of the forest cover in the Appalachian Mountains. Buildings and bridges are frequently carried away, and gravel and boulders are washed over the rich bottom lands.

In the mountains of far-away Italy the soil is poor, and so are the people. They have cut down nearly all the trees and for hundreds of years the brush and gra.s.s have been eaten so closely by the sheep and goats that few roots remain to hold the soil. It does not need to rain heavily there to cause the rivers to become muddy and swollen. The soil which once covered the slopes has been carried to the bays, and now there is land where s.h.i.+ps floated two thousand years ago.

[Ill.u.s.tration: _U. S. Forest Service_ Terraces of rock built by natives of China to aid in holding the soil.]

In Spain so much of the best soil has been lost that the people now do not raise enough food to support themselves, and much has to be imported from other lands.

France is a rich country still, in spite of the cutting of so much of the forest and the careless pasturing of the mountain slopes. The people are industrious and hard working and thus make a living in spite of the loss which they are suffering.

The Montenegrins are among the bravest people of Europe, but their land is barren and they enjoy few luxuries. Their country consists largely of limestone mountains, from which they have been cutting the trees for hundreds of years. There is but little soil and that is to be found in the hollows of the rocks. This soil is so precious that every bit, be it ever so small, is carefully cultivated.

In the mountains of Palestine and Syria the people have so completely destroyed the trees and gra.s.ses which Nature once planted there that it is difficult for them to raise enough to live upon. The rivers are muddy after every rain, and even the water from the melting snows picks up some of the soil and flows away with a dirty, yellow color.

When we reach China and Korea, we find that there the people have been most severely punished for their carelessness. The mountain sides have been torn by the rains and deeply gullied. The once smooth slopes upon which grew trees and gra.s.ses are now a ma.s.s of sharp ridges and deep hollows of bare earth. The water falling upon these mountains runs off in torrents, carrying even large boulders as it does in our Western deserts. Here and there the natives have built terraces of rock to aid in holding the soil, but many parts of the country are almost wholly deserted. The waters run off the mountains so quickly that they often form vast floods which spread over the lower valleys and plains. The floods destroy the crops and drown the people.

Eastward of China there is an arm of the Pacific Ocean known as the Yellow Sea. Why do you suppose this name was given to the sea? One of the great rivers of China, the Yangste-kiang, empties into it. The river rises in the barren mountains of which we have just been speaking, and it is continually bringing so much mud and sand that a whole sea is being filled. Long before a s.h.i.+p comes within sight of the land the waters are seen to be of a muddy, yellow color.

In the smaller valleys of Korea the natives build dikes along the rivers to keep the mountain floods from spreading sand and gravel over their rice fields. Every year they have to make the dikes higher as the river beds fill up.

Thus we see that all over the world people are suffering because they have not obeyed the laws which Nature has made for the protection of the soil.

CHAPTER THIRTEEN

THE USE AND CARE OF WATER

The ocean is the home of the water. The water would always remain in the ocean if it could, but the sun and air are continually at work stealing little particles away and sending them on long journeys.

The water particles are so small as they rise from the ocean that we cannot see them. By and by they crowd together and make the clouds that float across the sky. As soon as the clouds meet colder air, the little water particles rush together and thus become larger and larger until they grow so heavy that they can no longer float in the air, but must fall. Some of them fall into the ocean again, but others drop upon the land.

The raindrops that reach the land have many sorts of stories to tell before they again get back to the ocean. Some of them are at once s.n.a.t.c.hed up again and are started upon another journey. The thirsty air, whether over the ocean or over the land, is ever in search of water particles.

If the air is very cold, the clouds turn to snow instead of rain. The feathery flakes fall slowly through the air and form a soft white mantle over the earth. Those that fall on lofty mountains form great banks which may not entirely melt and turn to water until late in the summer.

The raindrops that fall where the slopes are steep, where Nature has grown little vegetation, or where men have destroyed the earth cover, have little to detain them and are soon on their way back to their home.

In their hasty journey they do much damage to the unprotected soil.

If the drops fall upon gentle slopes, or where there are marshes and lakes, or upon the forest with its decaying vegetation, or upon deep beds of gravel and sand, they are a long time getting back to the ocean.

[Ill.u.s.tration: _George J. Young_ The cool and shady stream before men came and cut the trees away so that the hot sun could get at it.]

We can in no way change the amount of rain that falls upon any part of the earth. We cannot call up a storm when we wish it, nor can we send it away when there has been rain enough. But there are many ways in which we can hasten or delay the return of the water to the ocean. Nature shows us some of these. The spongelike carpet underneath the forest holds the water until it has had time to soak into the earth from which it later emerges as springs. Nature forms basins on the heads of the rivers where a part of the water, instead of immediately flowing away, collects in the form of lakes. From these lakes the water runs away slowly instead of in torrential floods.

[Ill.u.s.tration: _H. W. Fairbanks_ The rotting tree trunks take up the rainwater like a sponge.]

Only a few places in our country have more rain than is really needed.

One of these is the region about the mouth of the Mississippi River upon the Gulf of Mexico. Another is upon the Northwest coast. Throughout the central part of the country the summer rains are sometimes too light to afford a full harvest. The rainfall upon the plains and valleys of the Southwest is so small that the only plants that can live there are those strange and curious forms that have become used to desert conditions. The only way in which these lands can be made useful to the farmer is by means of irrigation. To obtain water for irrigation we have either to go to the distant mountains and build reservoirs to collect the rains which fall there and then dig ca.n.a.ls to carry the water to the desert valleys, or to make use of some river flowing through them, if they are fortunate enough to have such a river. Can you think of any rivers that are used in this way?

[Ill.u.s.tration: _Brown Brothers_ The great Roosevelt Dam, in the Salt River irrigation project, Arizona.]

Although water sometimes seems the greatest blessing that we have, yet it may prove a curse if it is not looked after. If you give the water a chance to make gullies in your fields, you lose not only the water but the best of the soil also. If you cultivate your fields with care, most of the water will soak into the ground. If you are a wise farmer you know also that cultivation of the soil helps to hold the water, for it cannot escape through loose soil as it can through compact soil. Thus if you know how to handle both the water and the soil, you can, with only a little rain, accomplish a great deal.

[Ill.u.s.tration: Scene below an irrigation reservoir near Richfield, Idaho, showing a field irrigated by means of ca.n.a.ls and ditches.]

We can, then, hold or _conserve_ the water, first, by leaving the steeper slopes covered with vegetation; second, by keeping the soil loose; and, third, by building reservoirs to hold the floods. We can make use of the conserved water by carrying it in pipes or ditches to those regions where it is needed. We can get rid of too much water by draining the swamps, and building dikes to protect lowlands from river floods.

Let us now learn something of the different uses of water. Every one of our homes has its water supply. In the city the water comes through pipes from some distant reservoir. In the country the homes are so far apart that it is difficult to supply them in this way. The water in the streams is often not suitable for drinking, and if there are no springs near by it has to be obtained by some other means. Nearly everywhere in the earth under our feet water can be found by digging or boring a well.

Sometimes we have to go only a few feet, at other times many hundreds of feet. This water in the earth, or _ground water_, is of very great importance. It enables us to build our homes where we wish. Spring water is that which finds its way to the surface through some tiny crack or fissure in the rocks. How delicious is the pure, cold water that comes out of the shady hollow in the hills! You can form in your minds a picture of the rain falling on some distant mountain, of its soaking into the ground and finally reaching the little crevices in the rocks.

Along these crevices it may have crept for days and perhaps years until at last it found an outlet in some spring.

The great river flows by so quietly that we often forget in how many ways it is serving us. It serves not only those upon its banks but those who live hundreds of miles away and who, perhaps, have never seen it. It was the first and easiest means of travel used by our forefathers before there were any roads or railroads through the wilderness. It now aids in carrying on trade between different regions. If large and deep enough, it permits boats from all parts of the world to reach the very heart of our country.

Ca.n.a.ls might be called artificial rivers. They serve an important purpose in nearly level countries where Nature has placed no navigable river. Although ca.n.a.l boats usually move slowly, yet they can carry goods cheaper than railroads can. The Erie Ca.n.a.l, in connection with the Great Lakes and the Hudson River, makes it possible for us to go all the way by water from the heart of the continent to New York City. The Erie Ca.n.a.l has helped make New York City the greatest city in our country.

The ca.n.a.l across the Isthmus of Panama saves s.h.i.+ps a journey of many thousand miles around South America.

Rivers serve us in yet another way by affording water for irrigation. A great river like the Colorado flows through regions of many different climates. Some rivers become so small in the summer that it is necessary to build great reservoirs at their headwaters in order to insure a supply when the crops need it. But in the case of the Colorado this is not necessary. The headwaters of this river are among lofty mountains, where the melting snows and summer showers make the waters of the river higher in the early summer than at any other season of the year. Thus its great delta, the Colorado Desert, has become the home of many thousands of people.

Another use which we make of rivers is by putting the water to turning mill wheels. If you will turn to your geographies, you will find that nearly all the great manufacturing cities of our country have grown up around rapids or waterfalls, where some river tumbles over a ledge of rocks.

Once we had to build our mills close to the rivers to use the water power, but this is no longer necessary. Now we build electric-power plants by the rivers and carry electric energy more than a hundred miles to any place where we wish to use it. Electricity made from the distant mountain waterfall will do any kind of work for us wherever we carry it.

Thus we see that the river works for us in more than one way. After it has created power for our factories, it can be turned on to the thirsty fields, where it will serve us equally well.

[Ill.u.s.tration: _Great Western Power Company of California_ Electric-power plant on north fork of the Feather River, California, for generating electricity which is carried to distant places.]

CHAPTER FOURTEEN

COULD WE GET ALONG WITHOUT THE TREES?