THE SCHOOL BOOK OF FORESTRY
CHARLES LATHROP PACK
PRESIDENT OF THE AMERICAN TREE ASSOCIATION
THE AUTHOR GRATEFULLY ACKNOWLEDGES INFORMATION AND ASSISTANCE FROM THE WRITINGS AND REPORTS OF COL. W.B. GREELEY, U.S. FORESTER; COL. HENRY S. GRAVES, FORMER U.S. FORESTER; GIFFORD PINCHOT, FORMER U.S. FORESTER; DR. B.E. FERNOW, DR. J.W. TOUMEY, F.W. BESLEY, W.I. HUTCHINSON, R.H.D. BOERKER, PROF. NELSON C. BROWN, PROF. R.S. HOSMER, E.A. STERLING, R.S. KELLOGG, E.T. ALLEN, S. GORDON DORRANCE, DR. HUGH P. BAKER, ALFRED GASKILL, J.S. ILLICK, AND MANY OTHER LEADERS IN FORESTRY.
"THE PART OF GOOD CITIZENS"
A people without children would face a hopeless future; a country without trees is almost as helpless; forests which are so used that they cannot renew themselves will soon vanish, and with them all their benefits. When you help to preserve our forests or plant new ones you are acting the part of good citizens.
Our forests, with their billions of trees, are the backbone of agriculture, the skeleton of lumbering, and the heart of industry. Even now, in spite of their depletion, they are the cream of our natural resources. They furnish wood for the nation, pasture for thousands of cattle and sheep, and water supply for countless cities and farms. They are the dominions of wild life. Millions of birds, game animals, and fish live in the forests and the forest streams. The time is coming when our forests will be the greatest playgrounds of America. It is necessary that we preserve, protect, and expand our timberlands. By so doing we shall provide for the needs of future generations.
The forest is one of the most faithful friends of man. It provides him with materials to build homes. It furnishes fuel. It aids agriculture by preventing floods and storing the surplus rainfall in the soil for the use of farm crops. It supplies the foundation for all our railroads. It is the producer of fertile soils. It gives employment to millions of workmen. It is a resource which bountifully repays kind treatment. It is the best organized feature of the plant world. The forest is not merely a collection of different kinds of trees. It is a permanent asset which will yield large returns over long periods when properly managed.
Our forest fortune has been thoughtlessly squandered by successive generations of spendthrifts. Fortunately, it is not too late to rebuild it through cooeperative effort.
The work has been well begun, but it is a work of years, and it is to the youth of the country that we must look for its continuous expansion and perpetuation. A part of our effort must be directed toward familiarizing them with the needs and rewards of an intelligent forestry policy.
INTRODUCTION CHAPTER I. HOW TREES GROW AND MULTIPLY II. THE FOREST FAMILIES III. FORESTS AND FLOODS IV. WILD LIFE OF THE FOREST V. IMPORTANT FOREST TREES AND THEIR USES VI. THE GREATEST ENEMY OF THE FOREST—FIRE VII. INSECTS AND DISEASES THAT DESTROY FORESTS VIII. THE GROWTH OF THE FORESTRY IDEA IX. OUR NATIONAL FORESTS X. THE NATIONAL FORESTS OF ALASKA XI. PROGRESS IN STATE FORESTRY XII. THE PLAYGROUNDS OF THE NATION XIII. SOLVING OUR FORESTRY PROBLEMS XIV. WHY THE UNITED STATES SHOULD PRACTICE FORESTRY XV. WHY THE LUMBERMAN SHOULD PRACTICE FORESTRY XVI. WHY THE FARMER SHOULD PRACTICE FORESTRY XVII. PUTTING WOOD WASTE TO WORK XVIII. WOOD FOR THE NATION
Forest Fire Guard Stationed in a Tree Top Section of a Virgin Forest The Sequoias of California A Forest Ranger and His Forest Cabin Pine Which Yields Turpentine and Timber Forest Fires Destroy Millions of Dollars Worth of Timber Every Year Blackened Ruins of a Fire Swept Forest Forest Management Provides for Cutting Mature Trees Seed Beds in a Forest Nursery Sowing Forest Seed in an Effort to Grow a New Forest A Camping Ground in a National Forest Good Forests Mean Good Hunting and Fishing Young White Pine Seeded from Adjoining Pine Trees What Some Kinds of Timber Cutting Do to a Forest On Poor Soil Trees are More Profitable Than Farm Crops A Forest Crop on its Way to the Market
[Transcriber's note: "Section of a Virgin Forest" is the seventh (not the second) illustration in the book.]
HOW TREES GROW AND MULTIPLY
The trees of the forest grow by forming new layers of wood directly under the bark. Trees are held upright in the soil by means of roots which reach to a depth of many feet where the soil is loose and porous. These roots are the supports of the tree. They hold it rigidly in position. They also supply the tree with food. Through delicate hairs on the roots, they absorb soil moisture and plant food from the earth and pass them along to the tree. The body of the tree acts as a passage way through which the food and drink are conveyed to the top or crown. The crown is the place where the food is digested and the regeneration of trees effected.
The leaves contain a material known as chlorophyll, which, in the presence of light and heat, changes mineral substances into plant food. Chlorophyll gives the leaves their green color. The cells of the plant that are rich in chlorophyll have the power to convert carbonic-acid gas into carbon and oxygen. These cells combine the carbon and the soil water into chemical mixtures which are partially digested when they reach the crown of the tree. The water, containing salts, which is gathered by the roots is brought up to the leaves. Here it combines with the carbonic-acid gas taken from the air. Under the action of chlorophyll and sunlight these substances are split up, the carbon, oxygen and hydrogen being combined into plant food. It is either used immediately or stored away for future emergency.
Trees breathe somewhat like human beings. They take in oxygen and give off carbonic-acid gas. The air enters the tree through the leaves and small openings in the bark, which are easily seen in such trees as the cherry and birch. Trees breathe constantly, but they digest and assimilate food only during the day and in the presence of light. In the process of digestion and assimilation they give off oxygen in abundance, but they retain most of the carbonic acid gas, which is a plant food, and whatever part of it is not used immediately is stored up by the tree and used for its growth and development. Trees also give off their excess moisture through the leaves and bark. Otherwise they would become waterlogged during periods when the water is rising rapidly from the roots.
After the first year, trees grow by increasing the thickness of the older buds. Increase in height and density of crown cover is due to the development of the younger twigs. New growth on the tree is spread evenly between the wood and bark over the entire body of the plant. This process of wood production resembles a factory enterprise in which three layers of material are engaged. In the first two of these delicate tissues the wood is actually made. The inner side of the middle layer produces new wood while the outer side grows bark. The third layer is responsible for the production of the tough, outer bark. Year after year new layers of wood are formed around the first layers. This first layer finally develops into heartwood, which, so far as growth is concerned, is dead material. Its cells are blocked up and prevent the flow of sap. It aids in supporting the tree. The living sapwood surrounds the heartwood. Each year one ring of this sapwood develops. This process of growth may continue until the annual layers amount to 50 or 100, or more, according to the life of the tree.
One can tell the age of a tree by counting the number of annual rings. Sometimes, because of the interruption of normal growth, two false rings may be produced instead of a single true ring. However, such blemishes are easy for the trained eye to recognize. Heartwood does not occur in all varieties of trees. In some cases, where both heartwood and sapwood appear, it is difficult to distinguish between them as their colors are so nearly alike. Because it takes up so much moisture and plant food, sapwood rots much more quickly than heartwood. The sapwood really acts as a pipe line to carry water from the roots to the top of the tree. In some of our largest trees the moisture is raised as high as 300 feet or more through the sapwood.
Strange though it may seem, trees fight with each other for a place in the sunlight. Sprightly trees that shoot skyward at a swift pace are the ones that develop into the monarchs of the forest. They excel their mates in growth because at all times they are exposed to plenty of light. The less fortunate trees, that are more stocky and sturdy, and less speedy in their climb toward the sky, are killed out in large numbers each year. The weaker, spindly trees of the forest, which are slow growers, often are smothered out by the more vigorous trees.
Some trees are able to grow in the shade. They develop near or under the large trees of the forest. When the giants of the woodland die, these smaller trees, which previously were shaded, develop rapidly as a result of their freedom from suppression. In many cases they grow almost as large and high as the huge trees that they replace. In our eastern forests the hemlock often follows the white pine in this way. Spruce trees may live for many years in dense shade. Then finally, when they have access to plenty of light they may develop into sturdy trees. A tree that is a pigmy in one locality may rank as a giant in another region due to different conditions of growth and climate. For example, the canoe birch at its northern limit is a runt. It never grows higher than a few feet above the ground. Under the most favorable conditions in Florida, where this species thrives, such trees often tower to a height of 125 feet.
In sheltered regions the seeds of trees may fall, sprout and take root close to their parent trees. As a rule, the wind plays a prominent part in distributing seed in every section of the country. Pine and fir seeds are equipped with wings like those of a bird or an airplane. They enable the seeds to fly long distances on the wind before they drop to the ground and are covered with leaves. Maple seeds fly by means of double-winged sails which carry them far afield before they settle. Ash seeds have peculiar appendages which act like a skate-sail in transporting them to distant sections. Cottonwood seeds have downy wings which aid their flight, while basswood seeds are distributed over the country by means of parachute-like wings. The pods of the locust tree fall on the frozen ground or snow crust and are blown long distances from their source. On the other hand, oak, hickory, and chestnut trees produce heavy seeds which generally remain where they fall.
Squirrels are the most industrious foresters in the animal world. Each year they bury great quantities of tree seeds in hoards or caches hidden away in hollow logs or in the moss and leaves of the forest floor. Birds also scatter tree seed here, there, and everywhere over the forests and the surrounding country. Running streams and rivers carry seeds uninjured for many miles and finally deposit them in places where they sprout and grow into trees. Many seeds are carried by the ocean currents to distant foreign shores.
The decay of leaves and woodland vegetation forms rich and fertile soils in the forests, in which conditions are favorable for the development of new tree growth. When living tree seeds are exposed to proper amounts of moisture, warmth and air in a fertile soil, they will sprout and grow. A root develops which pushes its way down into the soil, while the leaf-bud of the plant, which springs from the other end of the seed, works its way upward toward the light and air. This leafy part of the seed finally forms the stem of the tree. But trees may produce plenty of seed and yet fail to maintain their proper proportion in the forest. This results because much of the seed is unsound. Even where a satisfactory supply of sound fertile seed is produced, it does not follow that the trees of that variety will be maintained in the forest, as the seed supply may be scattered in unfavorable positions for germination. Millions of little seedlings, however, start to grow in the forest each year, but only a small number survive and become large trees. This is because so many of the seedlings are destroyed by forest fires, cattle and sheep grazing, unfavorable soil and weather conditions, and many other causes.
Beech and chestnut trees and others of the broad-leaved type reproduce by means of sprouts as well as by seed. Generally, the young stumps of broad-leaved trees produce more sprouts than the stumps of older trees which have stood for some time. Among the cone-bearing trees reproduction by sprouts is rare. The redwood of California is one of the few exceptions. The pitch pine of the Eastern States produces many sprouts, few of which live and develop into marketable timber.
When trees are grown in nurseries, the practice is to sow the seed in special beds filled with rich soil. Lath screens are used as shade. They protect the young seedlings from the sun just as the parent trees would do in the forest. The seedbeds are kept well cultivated and free of weeds so that the seedlings may have the best opportunities for rapid growth. Generally the seeds are sown in the spring between March and May. Such seeds as the elms and soft maples, which ripen in the early summer, are sown as soon as possible after they are gathered. Practical tests have shown that thick sowings of tree seeds give the best results. There is little danger of weeds smothering out the seedlings under such conditions. After the seed has germinated the beds may be thinned so that the seedlings will have more room to develop.
During the fall of the same year, or in the following spring, the seedlings should be transplanted to nursery rows. Thereafter it is customary to transplant the young trees at least once again during damp weather. When the trees finally are robust and vigorous and have reached the age of two to five years, they are dug up carefully and set out permanently. The usual practice is to keep the seedlings one year in the seedbed and two years in the nursery rows before they are set out. Whether the transplanting should take place during the spring or fall depends largely on the climate and geography of the locality. Practical experience is the best guide in such matters.
Some farmers and land owners are now interested in setting out hardwood forests for commercial purposes. If they do not wish to purchase their seedlings from a reliable nursery-man, they can grow them from carefully selected seed planted in well-prepared seedbeds. The popular practice is to sow the seed in drills about 2 to 3 feet apart so that horses may be used for cultivation. The seeds are sown to a depth of 2 to 3 times their thickness. They are placed close enough in the drill so that from 12 to 15 seedlings to the linear foot result. In order to hasten the sprouting of the seeds, some planters soak them in cold water for several days before sowing. In the case of such hard-coated seed as the black locust or honey locust, it is best to soak them in hot water before planting.
THE FOREST FAMILIES
Trees are as queer in picking out places to live and in their habits of growth as are the peoples of the various races which inhabit the world. Some trees do best in the icy northland. They become weak and die when brought to warm climates. Others that are accustomed to tropical weather fail to make further growth when exposed to extreme cold. The appearance of Jack Frost means death to most of the trees that come from near the equator. Even on the opposite slopes of the same mountain the types of trees are often very different. Trees that do well on the north side require plenty of moisture and cool weather. Those that prosper on south exposures are equipped to resist late and early frosts as well as very hot sunshine. The moisture needs of different trees are as remarkable as their likes and dislikes for warmth and cold. Some trees attain large size in a swampy country. Trees of the same kind will become stunted in sections where dry weather persists.
In some parts of the United States forestry experts can tell where they are by the local tree growth. For example, in the extreme northern districts the spruce and the balsam fir are native. As one travels farther south these give way to little Jack pine and aspen trees. Next come the stately forests of white and Norway pine. Sometimes a few slow-growing hemlock trees appear in the colder sections. If one continues his journey toward the equator he will next pass through forests of broad-leaved trees. They will include oak, maple, beech, chestnut, hickory, and sycamore.
In Kentucky, which is a centre of the broad-leaved belt, there are several hundred different varieties of trees. Farther south, the cone-bearing species prevail. They are followed in the march toward the Gulf of Mexico by the tropical trees of southern Florida. If one journeys west from the Mississippi River across the Great Plains he finally will come to the Rocky Mountains, where evergreen trees predominate. If oak, maple, poplar, or other broad-leaved trees grow in that region, they occur in scattered stands. In the eastern forests the trees are close together. They form a leafy canopy overhead. In the forests of the Rockies the evergreens stand some distance apart so that their tops do not touch. As a result, these Western forests do not shade the ground as well as those in the east. This causes the soils of these forests to be much drier, and also increases the danger from fire.
The forests of western Washington and Oregon, unlike most timberlands of the Rocky Mountain Region, are as dense as any forests in the world. Even at midday it is as dark as twilight in these forests. The trees are gigantic. They tower 150 to 300 feet above the ground. Their trunks often are 6 feet or larger in diameter. They make the trees of the eastern forests look stunted. They are excelled in size only by the mammoth redwood trees of northern California and the giant Sequoias of the southern Sierras.
Differences of climate have largely influenced tree growth and types in this country. The distribution of tree families is changing all the time. It shifts just as the climate and other conditions change. Trees constantly strive among themselves for control of different localities. For a time one species will predominate. Then other varieties will appear and displace the ones already established. The distribution of trees changes very remarkably from one century to another. For example, in some sections, the red and black oaks are replacing the white oaks. Some trees are light-lovers. They require much more sunlight than others that do well under heavy shade. Oak trees require plenty of light; maples or beeches thrive on little light.
The seed of trees requiring little light may be scattered in a dense forest together with that of trees which need plenty of daylight in order to make normal growth. The seedlings that like shade will develop under such conditions while those that need light will pine away and die. Gradually the shade-loving trees will replace the light-loving trees in such a forest stand. Even the different trees of the same family often strive with one another for light and moisture. Each tree differs from every other one in shape and size. Trees will adapt themselves to the light and moisture conditions to which they are exposed. A tree that has access to plenty of moisture and sunlight grows evenly from the ground to its top with a bushy, wide-spreading crown. The same tree, if it grows in the shade, will reach a greater height but will have a small compact crown. Trees run a race in their rapidity of growth. The winners get the desirable places in the sunlight and prosper. The losers develop into stunted trees that often die, due to lack of light exposure. A better quality of lumber results from tall straight trees than that produced by the symmetrical, branching trees. That is why every forester who sets out trees tries to provide conditions which will make them grow tall and with the smallest possible covering of branches on the lower part of the trunks.
Where trees are exposed to strong winds, they develop deep and strong root systems. They produce large and strong trunks that can bend and resist violent winds which sway and twist them in every direction. Such trees are much stronger and sturdier than those that grow in a sheltered forest. The trees that are blown down in the forest provide space for the introduction and growth of new varieties. These activities are constantly changing the type of tree growth in the forest.
Our original forests which bordered the Atlantic coast line when America was first settled, were dense and impenetrable. The colonists feared the forests because they sheltered the hostile Indians who lurked near the white settlements. In time this fear of the forest developed into hatred of the forest. As a result, the colonists cut trees as rapidly as they could. In every way they fought back the wilderness. They and their children's children have worked so effectively that the original wealth of woodlands has been depleted. At present, cleared fields and cutover areas abound in regions that at one time were covered with magnificent stands of timber.
In many sections of the country our forests are now so reduced that they are of little commercial importance. However, these areas are not yet entirely denuded. Predictions have been made frequently that our woodlands would soon disappear. Scientific foresters report that such statements are incorrect. There are only a few districts in the country which probably will never again support much tree growth. Their denuded condition is due largely to the destruction of the neighboring mountain forests and to the activities of erosion. Under ordinary conditions, natural reforestation will maintain a satisfactory tree growth on lands where a practical system of forest protection is practiced. The complete removal of the forest is now accomplished only in fertile farming regions, where the agricultural value of the land is too high to permit it to remain longer in forest cover. Even in the Mississippi Valley and the Great Lakes belts there are still large areas of forest land. Most of the farms have woodlots which provide fuel, fencing, and some lumber. For the most part, these farm woodlots are abused. They have not been managed correctly. Fortunately, a change for the better is now evident. The farm woodlot owners are coming to appreciate the importance of protecting the trees for future use. In some cases, they are even replanting areas that have been cut over. There are large tracts of sandy, rocky and swampy land in these districts that are satisfactory for tree production. In fact, about all these fields are good for is the growing of timber. Campaigns are now under way to increase tree planting and develop the production of lands adapted for forestry which previously have been idle.
The United States of the future will not be a desert, tree-less country. However, immediate measures to save our remaining trees must be developed. The greater part of our virgin timber has already been felled. The aftermath forests, which succeed the virgin stand, generally are inferior. Our supplies of ash, black walnut and hickory, once abundant, are now seriously limited. Formerly, these mixed forests covered vast stretches of country which today support only a scant crop of young trees which will not be ready for market for many years. These second-growth stands will never approach in value or quality the original forests. Over large areas, poplar, white birch, and Jack pine trees now predominate on lands which formerly bore dense stands of white pine. In many places, scrubby underbrush and stunted trees occupy lands which heretofore have been heavy producers of marketable timber trees.
Generally speaking, farm lands should not be used for forestry purposes. On the other hand, some forest lands can be profitably cleared and used for agriculture. For example, settlers are felling trees and fighting stumps in northern Wisconsin, Michigan, and Minnesota. Some of these virgin lands are valuable for farming purposes, others are not. It is preferable that they should produce farm crops instead of tree crops if the land is best adapted to agricultural use. It is an economic necessity that all lands in this country best suited for farming purposes should be tilled. Our ever-increasing population demands that every acre of land useful for growing crops should be cleared and devoted to farming. Under such conditions, the settlers should reserve sufficient woodlands for their home needs, carefully distinguishing between the land that is best for agricultural purposes and the land that is best for forestry purposes, and thus doubling their resources.
Thoughtless lumbermen have pillaged millions of acres of our most productive forests. The early lumbermen wasted our woodland resources. They made the same mistakes as everyone else in the care and protection of our original forests. The greatest blame for the wasting of our lumber resources rests with the State and Federal authorities who permitted the depletion. Many of our lumbermen now appreciate the need of preserving and protecting our forests for future generations. Some of them have changed their policies and are now doing all in their power to aid forest conservation.
The ability of a properly managed forest to produce new crops of trees year after year promises us a future supply of wood sufficient for all our needs if only we will conserve our timberlands as they deserve. It is our duty to handle the forests in the same way that fertile farming fields are managed. That is to say, they should be so treated that they will yield a profitable money crop every year without reducing their powers of future production. Private owners and farmers are coming slowly to realize the grave importance of preserving and extending our woodlands. The public, the State and the Nation are now solidly behind the movement to improve our forestry and to safe-guard our forests. Several of the States, including New York and Pennsylvania, have purchased large areas of timberlands for State forests. These will be developed as future sources of lumber supply.
FORESTS AND FLOODS
Forests are necessary at the headwaters of streams. The trees break the force of the rain drops, and the forest floor, acting as a large sponge, absorbs rainfall and prevents run-off and floods. Unless there are forests at the sources of streams and rivers, floods occur. The spring uprisings of the Mississippi, Ohio and Missouri Rivers are due largely to the lack of forests at their headwaters. In the regions drained by these streams the run-off water is not absorbed as it should be. It flows unimpeded from the higher levels to the river valleys. It floods the river courses with so much water that they burst their banks and pour pell-mell over the surrounding country. Many floods which occur in the United States occur because we have cut down large areas of trees which formerly protected the sources of streams and rivers.
A grave danger that threatens western farming is that some time in the future the greater part of the vegetation and forest cover on the watersheds of that section may entirely disappear. Such a condition would cause floods after every heavy rain. The available supplies of rainwater which are needed for the thirsty crops would be wasted as flood waters. These floods would cause great damage in the valleys through which they rushed. The freshets would be followed by periods of water famine. The streams would then be so low that they could not supply the normal demands. Farmers would suffer on account of the lack of irrigation water. Towns and cities that depended on the mountain streams for their water supplies would be handicapped severely. In a thousand and one ways, a deficient water supply due to forest depletion would cause hardships and suffering in the regions exposed to such misfortune.
The important part which forests play in the development of our country is shown by the fact that from the streams of the National Forests over 700 western cities and towns, with an aggregate population of nearly 2,500,000, obtain their domestic water supply. The forests include 1266 irrigation projects and 325 water-power plants, in addition to many other power and irrigation companies which depend on the Government timberlands for water conservation and the regulation of rain water run-off and stream flow.
The National Forests aid greatly in conserving and making available for use the precious limited rainfall of the arid regions. That is why settlers in irrigated districts are deeply interested in the cutting of timber in the Federal woodlands. Destructive lumbering is never practiced in these forests. In its place has been substituted a system of management that assures the continued preservation of the forest-cover. Uncle Sam is paying special attention to the western water-sheds which supply reclamation and irrigation projects. He understands that the ability of the forest to regulate stream flow is of great importance. The irrigation farmers also desire a regular flow, evenly distributed, throughout the growing season.
One of the chief reasons for the establishment of the National Forest was to preserve the natural conditions favorable to stream flow. In a treeless country, the rise of the streams is a very accurate measure of the rainfall. In the region where forests are frequent, an ordinary rain is scarcely noticed in its effect on the stream. In a denuded district no natural obstacles impede the raindrops as they patter to the ground. The surface of the soil is usually hard. It is baked and dried out by the sun. It is not in condition to absorb or retain much of the run-off water, consequently, the rain water finds little to stop it as it swirls down the slopes. In torrents it rushes down the stream beds, like sheets of water flowing down the steep roof of a house.
Conditions are very different in a region where forest cover is abundant. In the forests, the tops of the trees catch much of the rain that falls. The leaves, twigs, branches and trunks of the trees also soak up considerable moisture. The amount of rainfall that directly strikes the ground is relatively small. The upper layer of the forested ground consists of a network of shrubs, and dead leaves, branches, and moss. This forest carpet acts like an enormous sponge. It soaks up the moisture which drops from the trees during a storm. It can absorb and hold for a time a rainfall of four or five inches. The water that finally reaches the ground sinks into the soil and is evaporated or runs off slowly. The portion that is absorbed by the soil is taken up by the roots of the trees and plants or goes to supply springs and watercourses.
The power of the trees and forest soil to absorb water regulates the rate at which the rainfall is fed to the streams and rivers. Frequently it takes weeks and even months for all the waters of a certain rain to reach these streams. This gradual supplying of water to the streams regulates their flow. It prevents floods and freshets. Careful observation and measurements have shown that unforested regions will discharge rain water at least twice as fast as will forested districts.
The stealing of soil by erosion occurs where run-off waters are not obstructed by forest growth. Silt, sand, and every other kind of soil are swept from their natural positions and spritted away by the foaming waters as they surge down the steep slopes. The stream or river which is flooded by these rushing waters roars down its narrow channel, tearing loose and undermining the jutting banks. In some cases, it will break from its ordinary course to flood exposed fields and to carry away more soil. As the speed of the stream increases its power to steal soil and carry it off is increased. Engineers report that the carrying power of a stream is increased 64 times when its rate of flow is doubled. If the flow of a river is speeded up ten times, this raging torrent will be able to carry one million times as much foreign material as it did when it was flowing at a normal rate of speed, causing inexpressible damage and destruction of life and property.
The protection afforded by forests on the water-sheds of streams furnishing the domestic water supply for cities and towns is becoming more fully realized. A large number of cities and towns have purchased and are maintaining municipal or communal forests for this very reason.
WILD LIFE OF THE FOREST
The forests of our country are the home and breeding grounds of hundreds of millions of birds and game animals, which the forests provide with food and shelter. If we had no forests, many of these birds and animals would soon disappear. The acorns and other nuts that the squirrels live upon are examples of the food that the forest provides for its residents.
In the clear, cold streams of the forests there are many different kinds of fish. If the forests were destroyed by cutting or fire many of the brooks and rivers would either dry up or the water would become so low that thousands of fish would die.
The most abundant game animals of forest regions are deer, elk, antelope and moose. Partridge, grouse, quail, wild turkeys and other game birds are plentiful in some regions. The best known of all the inhabitants of the woods are the squirrels. The presence of these many birds and animals adds greatly to the attractiveness of the forest.
Predatory animals, such as wolves, bears, mountain lions, coyotes and bobcats also live in the forest. They kill much livestock each year in the mountain regions of the Western States and they also prey on some species of bird life. The Federal and some State governments now employ professional hunters to trap and shoot these marauders. Each year the hunters kill thousands of predatory animals, thus saving the farmers and cattle and sheep owners many thousands of dollars.
Sportsmen are so numerous and hunting is so popular, that game refuges have to be provided in the forests and parks. Were it not for these havens of refuge where hunting is not permitted, some of our best known wild game and birds would soon be extinct. There are more than 11,640,648 acres of forest land in the government game refuges. California has 22 game refuges in her 17 National Forests. New Mexico has 19, while Montana, Idaho, Colorado, Washington and Oregon also have set aside areas of government forest land for that purpose. In establishing a game refuge, it is necessary to pick out a large area of land that contains enough good feed for both the summer and winter use of the animals that will inhabit it.
Livestock is sometimes grazed on game refuges, but only in small numbers, so that plenty of grass will be left for the support of the wild game. The refuges are under the direction of the Federal and the State game departments. To perpetuate game animals and game birds, it is not enough to pass game laws and forbid the shooting of certain animals and birds except at special times of the year; it is also necessary to provide good breeding grounds for the birds and animals where they will not be molested or killed. The game refuges provide such conditions.
The division of the range country into small farms and the raising of all kinds of crops have, it is claimed, done more to decrease our herds of antelope, elk, deer and other big game than have the rifles of the hunters. The plow and harrow have driven the wild life back into the rougher country. The snow becomes very deep in the mountains in the winter and the wild animals could not get food were it not for the game refuges in the low country. In the Yellowstone National Park country great bands of elk come down from the mountains during severe winters and have to be fed on hay to keep them from starving, as there is not sufficient winter range in this region to supply food for the thousands of elk.
Where the elk are protected from hunters they increase rapidly. This means that some of the surplus animals have to be killed, otherwise, the elk would soon be so numerous that they would seriously interfere with the grazing of domestic livestock. In different sections of the elk country, a count is made every few years on the breeding animals in each band. Whenever a surplus accumulates, the state permits hunters to shoot some of the elk. If the breeding herds get too small, no hunting is allowed. In this way, a proper balance is maintained.
In many states the wild game birds and fur-bearing animals of the forests are protected by closed seasons during which hunting is not permitted. It is realized that birds and animals are not only of interest to visitors to the forests, but that they, as well as the trees, are a valuable forest product.
IMPORTANT FOREST TREES AND THEIR USES
Of our native trees, the white pine is one of the best and most valuable. It is a tall straight tree that grows to a height of 100 to 150 feet. It produces wood that is light in weight and easy to work because it is so soft. At one time there were extensive pine forests in the northeastern states. Many of the trees were very large, and occasionally one may still see pine stumps that are 5 to 6 feet in diameter. White pine made fine lumber for houses and other buildings and this timber was among the first to be exhausted in the country.
Spruce trees have long furnished the bulk of the woodpulp used in making our supplies of paper. These trees live in the colder climates of the northern states. They like to grow in low, wet localities close to lakes or rivers. The spruces generally do not grow higher than 75-100 feet. The wood is soft like pine and even whiter in color. The aboriginal Indians used the roots of the spruce trees as thread, twine and rope.
The cedar trees, which are landmarks in many of our northern states, yield light, soft, durable wood that is useful in making poles, fence posts, lead pencils and cedar chests. The wood of the red cedar gives off a peculiar odor which is said to keep moths away from clothes stored in cedar chests, but it is the close construction of the chest which keeps them out. These trees are becoming scarce in all parts of the country. Cedars generally are small trees that grow slowly and live a long time. The outside wood is white and the heartwood is red or yellow. Cedar posts last a long time and are excellent for use in farm fences.
Chestnut blight, which destroys entire forests of chestnut timber, is gradually exhausting our supplies of this wood. Chestnut timber has long been used for railroad ties, fence posts and in the manufacture of cheap furniture. The wood is soft and brown in color. The bark and wood are treated at special plants in such a way that an extract which is valuable for tanning leather is obtained. Chestnut trees are upstanding, straight trees that tower 80 to 100 feet above the ground. The extinction of our chestnut forests threatens as no effectual control measures for checking the chestnut blight disease over large areas has yet been discovered.
The yellow poplar or tulip poplar furnishes timber for the manufacture of furniture, paper, the interior of railroad cars and automobiles. The dugouts of the early settlers and Indians were hewed out of poplar logs. These boats were stronger than those made of canoe birch. Poplar wood is yellow in color and soft in texture. The poplar is the largest broad-leaf tree in this country and the trees are of great size and height. Some specimens found in the mountains of the South have been over 200 feet high and 8 to 10 feet in diameter, while poplars 125 to 150 feet high are quite common.
Among our most useful and valuable trees are the white oak, and its close kin, the red oak, which produce a brown-colored, hard wood of remarkable durability. The white oak is the monarch of the forest, as it lives very long and is larger and stronger than the majority of its associates. The timber is used for railroad ties, furniture, and in general construction work where tough, durable lumber is needed. Many of our wooden ships have been built of oak. The white oaks often grow as high as 100 feet and attain massive dimensions. The seeds of the white oaks are light brown acorns, which are highly relished by birds and animals. Many southern farmers range their hogs in white oak forests so that the porkers can live on the acorn crop.
Beech wood is strong and tough and is used in making boxes and barrels and casks for the shipment of butter, sugar and other foods. It makes axles and shafts for water-wheels that will last for many years. The shoes worn by Dutch children are generally made of beech. The wood is red in color. The beech tree is of medium size growing to a height of about 75 feet above the ground. There is only one common variety of beech tree in this country.
Hickory trees are very popular because they produce sweet, edible nuts. The hickory wood is exceedingly strong and tough and is used wherever stout material is needed. For the spokes, wheels and bodies of buggies and wagons, for agricultural implements, for automobile wheels and for handles, hickory is unexcelled. The shafts of golf clubs as well as some types of base-ball bats are made of hickory. Most hickory trees are easy to identify on account of their shaggy bark. The nuts of the hickory, which ripen in the autumn, are sweet, delicious and much in demand.
Our native elm tree is stately, reaching a height of 100 feet and a diameter of 5 to 6 feet or more. It is one of our best shade trees. Elm wood is light brown in color and very heavy and strong. It is the best available wood for making wagon wheel hubs and is also used largely for baskets and barrels. The rims of bicycle wheels generally are made of elm.
The canoe birch is a tree which was treasured by the early Indians because it yielded bark for making canoes. Birch wood is used in making shoe lasts and pegs because of its strength and light weight, and the millions of spools on which cotton is wound are made of birch wood. School desks and church furniture, also, are made of birch. The orange-colored inner bark of the birch tree is so fine and delicate that the early settlers could use it as they would paper. No matter whether birch wood is green or dry, it will burn readily. The birch was the most useful tree of the forest to the Indians. Its bark was used not only for making their canoes, but also for building their wigwams. They even dried and ground the inner bark into a flour which they used as a food.
The northern sugar maple is another tree which is a favorite in all sections where it is grown. This tree yields a hard wood that is the best and toughest timber grown in some localities. The trees grow to heights of 75 to 100 feet and attain girths of 5 to 9 feet. Maple lumber is stout and heavy. It makes fine flooring and is used in skating rinks and for bowling alleys. Many pianos are made of maple. Wooden dishes and rolling pins are usually made from maple wood. During the spring of the year when the sap is flowing, the average mature maple tree will yield from fifteen to twenty gallons of sap in a period of three to four weeks. This sap is afterwards boiled down to maple syrup and sugar.
Hemlock trees, despite the fact that they rank among the most beautiful trees of the forest, produce lumber which is suitable only for rough building operations. The wood is brown and soft and will not last long when exposed to the weather. It cracks and splits easily because it is so brittle. Hemlock is now of considerable importance as pulpwood for making paper. For many years, a material important for tanning leather has been extracted in large amounts from the bark of hemlock trees.
One of the most pleasing uses to which the balsam fir is put is as Christmas trees. Sometimes it is used in making paper pulp. The balsam fir seldom grows higher than 50 feet or thicker than 12 inches. The leaves of this tree have a very sweet odor and are in demand at Christmas time. Foresters and woodsmen often use balsam boughs to make their beds and pillows when camping in the woods.
Our native supplies of hardwoods and softwoods are used for general building purposes, for farm repairs, for railroad ties, in the furniture and veneer industry, in the handle industry, and in the vehicle and agricultural implement industries. On the average each American farmer uses about 2,000 board feet of lumber each year. New farm building decreased in the several years following the World War, due to the high price of lumber and labor. As a result of this lack of necessary building, millions of dollars worth of farm machinery stood out in the weather. Livestock lacked stables in some sections. Very little building was done in that period in two hundred and fifty prosperous agricultural counties in thirty-two different states.
The railroads consume about 15 per cent. of our total lumber cut. They use between 100,000,000 and 125,000,000 railroad ties a year. It used to be that most of the cross-ties were of white oak cut close to the places where they were used. Now Douglas fir, southern pine and other woods are being used largely throughout the Middle Western and Eastern States. The supply of white oak ties is small and the prices are high. Some years ago, when white oak was abundant, the railroads that now are using other cross-ties would not have even considered such material for use in their roadbeds. The fact that other ties are now being used emphasizes the fact that we are short on oak timber in the sections where this hardwood formerly was common.
The furniture industry uses hardwoods of superior grade and quality. The factories of this industry have moved from region to region as the supply of hardwoods became depleted. Originally, these factories were located in the Northeastern States. Then, as the supplies of hardwood timber in those sections gave out, they moved westward. They remained near the Corn Belt until the virgin hardwood forests of the Middle West were practically exhausted. The furniture industry is now largely dependent on what hardwoods are left in the remote sections of the Southern Appalachians and the lower Mississippi Valley. When these limited supplies are used up, there will be very little more old-growth timber in the country for them to use.
The furniture, veneer, handle, vehicle, automobile and agricultural implement industries all are in competition for hardwood timber. The furniture industry uses 1,250,000,000 feet of high-grade hardwood lumber annually. Production of timber of this type for furniture has decreased as much as 50 per cent. during the past few years. It is now difficult for the furniture factories and veneer plants to secure enough raw materials. Facilities for drying the green lumber artificially are few. It used to be that the hardwood lumber was seasoned for six to nine months before being sold. Furniture dealers now have to buy the material green from the sawmills. Competition has become so keen that buyers pay high prices. They must have the material to keep their plants running and to supply their trade.
The veneer industry provides furniture manufacturers, musical instrument factories, box makers and the automobile industry with high-grade material. The industry uses annually 780,000,000 board feet of first quality hardwood cut from virgin stands of timber. Red gum and white oak are the hardwoods most in demand. In the Lake States, a branch of the veneer industry which uses maple, birch and basswood is located. Oak formerly was the most important wood used. Now red gum has replaced the oak, as the supplies of the latter timber have dwindled. At present there is less than one-fourth of a normal supply of veneer timber in sight. Even the supplies in the farmers' woodlands are being depleted. The industry is now largely dependent on the timber of the southern Mississippi Valley. The veneer industry requires best-grade material. Clear logs are demanded that are at least 16 inches in diameter at the small end. It is getting harder every year to secure such logs. Like the furniture industry, the veneer mills lack adequate supplies of good timber.
No satisfactory substitutes for the hickory and ash used in the handle industry have yet been found. About the only stocks of these timbers now left are in the Southern States. Even in those parts the supplies are getting short and it is necessary to cut timber in the more remote sections distant from the railroad. The ash shortage is even more serious than that of hickory timber. The supplies of ash in the Middle West States north of the Ohio River are practically exhausted. The demand for ash and hickory handles is larger even than before the World War. The entire world depends on the United States for handles made from these woods. Handle dealers are now willing to pay high prices for ash and hickory timber. Some of them prepared for the shortage by buying tracts of hardwood timber. When these reserves are cut over, these dealers will be in the same position as the rest of the trade.
Ash and hickory are in demand also by the vehicle and agricultural implement industries. They also use considerable oak and compete with the furniture industry to secure what they need of this timber. Most of these plants are located in the Middle West but they draw their timber chiefly from the South. Hickory is a necessary wood to the vehicle industry for use in spokes and wheels. The factories exert every effort to secure adequate supplies of timber from the farm woodlands, sawmills and logging camps. The automobile industry now uses considerable hickory in the wheels and spokes of motor cars.
Most of the stock used by the vehicle industry is purchased green. Neither the lumber nor vehicle industry is equipped with enough kilns for curing this green material. The losses in working and manufacturing are heavy, running as high as 40 per cent. Many substitutes for ash, oak and hickory have been tried but they have failed to prove satisfactory. On account of the shortage and the high prices of hickory, vehicle factories are using steel in place of hickory wherever possible. Steel is more expensive but it can always be secured in quantity when needed. Furthermore, it is durable and very strong.
Thus we see that our resources of useful soft woods and hard woods have both been so diminished that prompt reforestation of these species is an urgent necessity.
THE GREATEST ENEMY OF THE FOREST—FIRE
Our forests are exposed to destruction by many enemies, the worst of which is fire. From 8,000,000 to 12,000,000 acres of forest lands annually are burned over by destructive fires. These fires are started in many different ways. They may be caused by sparks or hot ashes from a locomotive. Lightning strikes in many forests every summer, particularly those of the Western States, and ignites many trees. In the South people sometimes set fires in order to improve the grazing. Settlers and farmers who are clearing land often start big brush fires that get out of their control. Campers, tourists, hunters, and fishermen are responsible for many forest fires by neglecting to extinguish their campfires. Sparks from logging engines also cause fires. Cigar and cigarette stubs and burning matches carelessly thrown aside start many forest fires. Occasionally fires are also maliciously set by evil-minded people.
The officers of the National Forests in the West have become very expert in running down the people who set incendiary fires. They collect evidence at the scene of the fire, such as pieces of letters and envelopes, matches, lost handkerchiefs and similar articles. They hunt for foot tracks and hoof marks. They study automobile tire tracks. They make plaster of Paris impressions of these tracks. They follow the tracks—sometimes Indian fashion. Often there are peculiarities about the tracks which lead to the detection and punishment of the culprits. A horse may be shod in an unusual manner; a man may have peculiar hob nails or rubber heels on his boots or else his footprints may show some deformity. The forest rangers play the parts of detectives very well. This novel police work has greatly reduced the number of incendiary fires.
A forest fire may destroy in a few hours trees that required hundreds of years to grow. A heavy stand of timber may be reduced to a desolate waste because some one forgot to put out a campfire. Occasionally large forest fires burn farm buildings and homes and kill hundreds of people. During the dry summer season when a strong wind is blowing, the fire will run for many miles. It always leaves woe and desolation in its wake. A mammoth forest fire in Wisconsin many years ago burned over an area of two thousand square miles. It killed about fourteen hundred people and destroyed many millions of dollars worth of timber and other property. A big forest fire in Michigan laid waste a tract forty miles wide and one hundred and eighty miles long. More than four billion feet of lumber, worth $10,000,000, was destroyed and several hundred people lost their lives. In recent years, a destructive forest fire in Minnesota caused a loss of $25,000,000 worth of timber and property.
There are several different kinds of forest fires. Some burn unseen two to four feet beneath the surface of the ground. Where the soil contains much peat, these fires may persist for weeks or even months. Sometimes, they do not give off any noticeable smoke. Their fuel is the decaying wood, tree roots and similar material in the soil. These underground fires can be stopped only by flooding the area or by digging trenches down to the mineral soil. The most effectual way to fight light surface fires is to throw sand or earth on the flames. Where the fire has not made much headway, the flames can sometimes be beaten out with green branches, wet gunny sacks or blankets. The leaves and debris may be raked away in a path so as to impede their advance.
Usually in the hardwood forests, there is not much cover, such as dry leaves, on the ground. Fires in these forests destroy the seedlings and saplings, but do not usually kill the mature trees. However, they damage the base of the trees and make it easy for fungi and insects to enter. They also burn the top soil and reduce the water-absorbing powers of the forest floor. In thick, dense evergreen forests where the carpet is heavy, fires are much more serious. They frequently kill the standing trees, burning trunks and branches and even following the roots deep into the ground. Dead standing trees and logs aid fires of this kind. The wind sweeps pieces of burning bark or rotten wood great distances to kindle new fires. When they fall, dead trees scatter sparks and embers over a wide belt. Fires also run along the tops of the coniferous trees high above the ground. These are called "crown-fires" and are very difficult to control.
The wind plays a big part in the intensity of a forest fire. If the fire can be turned so that it will run into the wind, it can be put out more easily. Fires that have the wind back of them and plenty of dry fuel ahead, speed on their way of destruction at a velocity of 5 to 10 miles an hour, or more. They usually destroy everything in their course that will burn, and waste great amounts of valuable timber. Wild animals, in panic, run together before the flames. Settlers and farmers with their families flee. Many are overtaken in the mad flight and perish. The fierce fires of this type can be stopped only by heavy rain, a change of wind, or by barriers which provide no fuel and thus choke out the flames.
Large fires are sometimes controlled by back-firing. A back-fire is a second fire built and so directed as to run against the wind and toward the main fire. When the two fires meet, both will go out on account of lack of fuel. When properly used by experienced persons, back-fires are very effectual. In inexperienced hands they are dangerous, as the wind may change suddenly or they may be lighted too soon. In such cases they often become as great a menace as the main fire. Another practical system of fighting fires is to make fire lines around the burning area. These fire lines or lanes as they are sometimes called, are stretches of land from which all trees and shrubs have been removed. In the centre of the lines a narrow trench is dug to mineral soil or the lines are plowed or burned over so that they are bare of fuel. Such lines also are of value around woods and grain fields to keep the fire out. They are commonly used along railroad tracks where locomotive sparks are a constant source of fire dangers.
Our forests, on account of their great size and the relatively small man force which guards them, are more exposed to fire dangers than any other woodlands in the world. The scant rainfall of many of the western states where great unbroken areas of forest are located increases the fire damages. The fact that the western country in many sections is sparsely settled favors destruction by forest fires. The prevalence of lightning in the mountains during the summer adds farther to the danger. One of the most important tasks of the rangers in the Federal forests is to prevent forest fires.
During the fire season, extra forest guards are kept busy hunting for signs of smoke throughout the forests. The lookouts in their high towers, which overlook large areas of forest, watch constantly for smoke, and as soon as they locate signs of fire they notify the supervisor of the forest. Lookouts use special scientific instruments which enable them to locate the position of the fires from the smoke. At the supervisor's headquarters and the ranger stations scattered through the forests, equipment, horses and automobiles are kept ready for instant use when a fire is reported. Telephone lines and radio sets are used to spread the news about fires that have broken out.
From five thousand to six thousand forest fires occur each year in the National Forests of our country. To show how efficient the forest rangers are in fighting fires, it is worthy of note that by their prompt actions, 80 per cent. of these fires are confined to areas of less than ten acres each, while only 20 per cent. spread over areas larger than ten acres. Lightning causes from 25 to 30 per cent. of the fires. The remaining 70 or 75 per cent. are classed as "man-caused fires," which are set by campers, smokers, railroads, brush burners, sawmills and incendiaries. The total annual loss from forest fires in the Federal forests varies from a few hundred thousands of dollars in favorable years to several million in particularly bad fire seasons. During the last few years, due to efficient fire-fighting methods, the annual losses have been steadily reduced.
The best way of fighting forest fires is to prevent them. The forest officers do their best to reduce the chances for fire outbreak in the Government woodlands. They give away much dead timber that either has fallen or still is standing. Lumbermen who hold contracts to cut timber in the National Forest are required to pile and burn all the slashings. Dry grass is a serious fire menace. That is why grazing is encouraged in the forests. Rangers patrol the principal automobile roads to see that careless campers and tourists have not left burning campfires. Railroads are required to equip their locomotives with spark-arresters. They also are obliged to keep their rights of way free of material which burns readily. Spark-arresters are required also on logging engines.
The National and State Forests are posted with signs and notices asking the campers and tourists to be careful with campfires, tobacco and matches. Advertisements are run in newspapers, warning people to be careful so as not to set fire to the forests. Exhibits are made at fairs, shows, community meetings and similar gatherings, showing the dangers from forest fires and how these destructive conflagrations may be controlled. Every possible means is used to teach the public to respect and protect the forests.
For many years, the United States Forest Service and State Forestry Departments have been keeping a record of forest fires and their causes. Studies have been made of the length and character of each fire season. Information has been gathered concerning the parts of the forest where lightning is most likely to strike or where campfires are likely to be left by tourists. The spots or zones of greatest fire danger are located in this way and more forest guards are placed in these areas during the dangerous fire season. Careful surveys of this kind are aiding greatly in reducing the number of forest fires.
In trying to get all possible information about future weather conditions, the Forestry Departments cooeperate with the United States Weather Bureau. When the experts predict that long periods of dry weather or dangerous storms are approaching, the forest rangers are especially watchful, as during such times, the menace to the woods is greatest. The rangers also have big fire maps which they hang in their cabins. These maps show the location of dangerous fire areas, roads, trails, lookout-posts, cities, towns and ranches, sawmills, logging camps, telephone lines, fire tool boxes and other data of value to fire fighters. All this information is so arranged as to be readily available in time of need. It shows where emergency fire fighters, tools and food supplies can be secured, and how best to attack a fire in any certain district. A detailed plan for fighting forest fires is also prepared and kept on file at every ranger station.
The following are six rules which, if put in practice, will help prevent outbreaks of fires:
1. Matches.—Be sure your match is out. Break it in two before you throw it away.
2. Tobacco.—Throw pipe ashes and cigar or cigarette stubs in the dust of the road and stamp or pinch out the fire before leaving them. Don't throw them into the brush, leaves or needles.
3. Making camp.—Build a small campfire. Build it in the open, not against a tree or log, or near brush. Scrape away the trash from all around it.
4. Leaving camp.—Never leave a campfire, even for a short time, without quenching it with water or earth. Be sure it is OUT.
5. Bonfires.—Never build bonfires in windy weather or where there is the slightest danger of their escaping from control. Don't make them larger than you need.
6. Fighting fires.—If you find a fire, try to put it out. If you can't, get word of it to the nearest United States forest ranger or State fire warden at once.
Remember "minutes count" in reporting forest fires.
INSECTS AND DISEASES THAT DESTROY FORESTS
Forest insects and tree diseases occasion heavy losses each year among the standing marketable trees. Insects cause a total loss of more than $100,000,000 annually to the forest products of the United States. A great number of destructive insects are constantly at work in the forests injuring or killing live trees or else attacking dead timber. Forest weevils kill tree seeds and destroy the young shoots on trees. Bark and timber beetles bore into and girdle trees and destroy the wood. Many borers and timber worms infest logs and lumber after they are cut and before they are removed from the forest. This scattered work of the insects here, there, and everywhere throughout the forests causes great damage.
Different kinds of flies and moths deposit their eggs on the leaves of the trees. After the eggs hatch, the baby caterpillars feed on the tender, juicy leaves. Some of the bugs destroy all the leaves and thus remove an important means which the tree has of getting food and drink. Wire worms attack the roots of the tree. Leaf hoppers suck on the sap supply of the leaves. Leaf rollers cause the leaves to curl up and die. Trees injured by fire fall easy prey before the attacks of forest insects. It takes a healthy, sturdy tree to escape injury by these pirates of the forests. There are more than five hundred insects that attack oak trees and at least two hundred and fifty different species that carry on destruction among the pines.
Insect pests have worked so actively that many forests have lost practically all their best trees of certain species. Quantities of the largest spruce trees in the Adirondacks have been killed off by bark beetles. The saw-fly worm has killed off most of the mature larches in these eastern forests. As they travel over the National and State Forests, the rangers are always on the watch for signs of tree infection. Whenever they notice red-brown masses of pitch and sawdust on the bark of the trees, they know that insects are busy there. Where the needles of a pine or spruce turn yellow or red, the presence of bark beetles is shown. Signs of pitch on the bark of coniferous trees are the first symptoms of infection. These beetles bore through the bark and into the wood. There they lay eggs. The parent beetles soon die but their children continue the work of burrowing in the wood. Finally, they kill the tree by making a complete cut around the trunk through the layers of wood that act as waiters to carry the food from the roots to the trunk, branches and leaves. The next spring these young develop into full-grown beetles, and come out from the diseased tree. They then attack new trees.
When the forest rangers find evidences of serious infection, they cut down the diseased trees. They strip the bark from the trunk and branches and burn it in the fall or winter when the beetles are working in the bark and can be destroyed most easily. If the infection of trees extends over a large tract, and there is a nearby market for the lumber the timber is sold as soon as possible. Trap trees are also used in controlling certain species of injurious forest insects. Certain trees are girdled with an ax so that they will become weakened or die, and thus provide easy means of entrance for the insects. The beetles swarm to such trees in great numbers. When the tree is full of insects, it is cut down and burned. In this way, infections which are not too severe can often be remedied.
The bark-boring beetles are the most destructive insects that attack our forests. They have wasted enormous tracts of pine timber throughout the southern states. The eastern spruce beetle has destroyed countless feet of spruce. The Engelmann spruce beetle has devastated many forests of the Rocky Mountains. The Black Hills beetle has killed billions of feet of marketable timber in the Black Hills of South Dakota. The hickory bark beetle, the Douglas fir beetle and the larch worm have been very destructive.
Forest fungi cause most of the forest tree diseases. A tree disease is any condition that prevents the tree from growing and developing in a normal, healthy manner. Acid fumes from smelters, frost, sunscald, dry or extremely wet weather, all limit the growth of trees. Leaf diseases lessen the food supplies of the trees. Bark diseases prevent the movement of the food supplies. Sapwood ailments cut off the water supply that rises from the roots. Seed and flower diseases prevent the trees from producing more of their kind.
Most of the tree parasites can gain entrance to the trees only through knots and wounds. Infection usually occurs through wounds in the tree trunk or branches caused by lightning, fire, or by men or animals. The cone-bearing trees give off pitch to cover such wounds. In this way they protect the injuries against disease infection. The hardwood trees are unable to protect their wounds as effectively as the evergreens. Where the wound is large, the exposed sapwood dies, dries out, and cracks. The fungi enter these cracks and work their way to the heartwood. Many of the fungi cannot live unless they reach the heartwood of the tree. Fires wound the base and trunks of forest trees severely so that they are exposed to serious destruction by heartrot.
Foresters try to locate and dispose of all the diseased trees in the State and Government forests. They strive to remove all the sources of tree disease from the woods. They can grow healthy trees if all disease germs are kept away from the timberlands. Some tree diseases have become established so strongly in forest regions that it is almost impossible to drive them out. For example, chestnut blight is a fungous disease that is killing many of our most valuable chestnut trees. The fungi of this disease worm their way through the holes in the bark of the trees, and spread around the trunk. Diseased patches or cankers form on the limbs or trunk of the tree. After the canker forms on the trunk, the tree soon dies. Chestnut blight has killed most of the chestnut trees in New York and Pennsylvania. It is now active in Virginia and West Virginia and is working its way down into North and South Carolina.
Diseased trees are a menace to the forest. They rob the healthy trees of space, light and food. That is why it is necessary to remove them as soon as they are discovered. In the smaller and older forests of Europe, tree surgery and doctoring are practised widely. Wounds are treated and cured and the trees are pruned and sprayed at regular intervals. In our extensive woods such practices are too expensive. All the foresters can do is to cut down the sick trees in order to save the ones that are sound.
There is a big difference between tree damages caused by forest insects and those caused by forest fungi and mistletoe. The insects are always present in the forest. However, it is only occasionally that they concentrate and work great injury and damage in any one section. At rare intervals, some very destructive insects may centre their work in one district. They will kill a large number of trees in a short time. They continue their destruction until some natural agency puts them to flight. The fungi, on the other hand, develop slowly and work over long periods. Sudden outbreaks of fungous diseases are unusual.
Heavy snows, lightning and wind storms also lay low many of the tree giants of the forest. Heavy falls of snow may weigh down the young, tall trees to such an extent that they break. Lightning—it is worst in the hills and mountains of the western states—may strike and damage a number of trees in the same vicinity. If these trees are not killed outright, they are usually damaged so badly that forest insects and fungi complete their destruction.
Big trees are sometimes uprooted during forest storms so that they fall on younger trees and cripple and deform them. Winds benefit the forests in that they blow down old trees that are no longer of much use and provide space for younger and healthier trees to grow. Usually the trees that are blown down have shallow roots or else are situated in marshy, wet spots so that their root-hold in the soil is not secure. Trees that have been exposed to fire are often weakened and blown down easily.
Where excessive livestock grazing is permitted in young forests considerable damage may result. Goats, cattle and sheep injure young seedlings by browsing. They eat the tender shoots of the trees. The trampling of sheep, especially on steep hills, damages the very young trees. On mountain sides the trampling of sheep frequently breaks up the forest floor of sponge-like grass and debris and thus aids freshets and floods. In the Alps of France sheep grazing destroyed the mountain forests and, later on, the grass which replaced the woods. Destructive floods resulted. It has cost the French people many millions of dollars to repair the damage done by the sheep.
The Federal Government does its best to keep foreign tree diseases out of the United States. As soon as any serious disease is discovered in foreign countries the Secretary of Agriculture puts in force a quarantine against that country. No seed or tree stock can be imported. Furthermore, all the new species of trees, cuttings or plants introduced to this country are given thorough examination and inspection by government experts at the ports where the products are received from abroad. All diseased trees are fumigated, or if found diseased, destroyed. In this manner the Government protects our country against new diseases which might come to our shores on foreign plants and tree stock.
THE GROWTH OF THE FORESTRY IDEA
Our forests of the New World were so abundant when the early settlers landed on the Atlantic Coast that it was almost impossible to find enough cleared land in one tract to make a 40-acre farm. These thick, dense timberlands extended westward to the prairie country. It was but natural, therefore, that the forest should be considered by these pioneers as an obstacle and viewed as an enemy. Farms and settlements had to be hewed out of the timberlands, and the forests seemed inexhaustible.
Experts say that the original, virgin forests of the United States covered approximately 822,000,000 acres. They are now shrunk to one-sixth of that area. At one time they were the richest forests in the world. Today there are millions of acres which contain neither timber nor young growth. Considerable can be restored if the essential measures are started on a national scale. Such measures would insure an adequate lumber supply for all time to come.
Rules and regulations concerning the cutting of lumber and the misuse of forests were suggested as early as the seventeenth century. Plymouth Colony in 1626 passed an ordinance prohibiting the cutting of timber from the Colony lands without official consent. This is said to be the first conservation law passed in America. William Penn was one of the early champions of the "Woodman, spare that tree" slogan. He ordered his colonists to leave one acre of forest for every five acres of land that were cleared.
In 1799 Congress set aside $200,000 for the purchase of a small forest reserve to be used as a supply source of ship timbers for the Navy. About twenty-five years later, it gave the President the power to call upon the Army and Navy whenever necessary to protect the live oak and red cedar timber so selected in Florida. In 1827, the Government started its first work in forestry. It was an attempt to raise live oak in the Southern States to provide ship timbers for the Navy. Forty years later, the Wisconsin State Legislature began to investigate the destruction of the forests of that state in order to protect them and prolong their life. Michigan and Maine, in turn, followed suit. These were some of the first steps taken to study our forests and protect them against possible extinction.
The purpose of the Timber Culture Act passed by Congress in 1873 was to increase national interest in reforestation. It provided that every settler who would plant and maintain 40 acres of timber in the treeless sections should be entitled to secure patent for 160 acres of the public domain—that vast territory consisting of all the states and territories west of the Mississippi, except Texas, as well as Ohio, Indiana, Illinois, Michigan, Wisconsin, Florida, Alabama and Mississippi. This act, as well as several State laws, failed because the settlers did not know enough about tree planting. The laws also were not effective because they did not prevent dishonest practices.
In 1876, the first special agent in forestry was appointed by the Commissioner of Agriculture to study the annual consumption, exportation and importation of timber and other forest products, the probable supply for future wants, and the means best adapted for forest preservation. Five years later, the Division of Forestry was organized as a branch of the Department of Agriculture. It was established in order to carry on investigations about forestry and how to preserve our trees.
For some nine years the Division of Forestry was nothing more than a department of information. It distributed technical facts and figures about the management of private woodlands and collected data concerning our forest resources. It did not manage any of the Government timberlands because there were no forest reserves at that time. It was not until 1891 that the first forest reserve, the Yellowstone Park Timberland Reserve, was created by special proclamation of President Harrison. Later it became part of the National Park reserves. Although the Division of Forestry had no special powers to oversee and direct the management of the forest reserves, during the next six years a total of 40,000,000 acres of valuable timberland were so designated and set aside. At the request of the Secretary of the Interior, the National Academy of Sciences therefore worked out a basis for laws governing national forests. Congress enacted this law in 1897. Thereafter the Department of the Interior had active charge of the timberlands. At that time little was known scientifically about the American forests. There were no schools of forestry in this country. During the period 1898-1903, several such schools were established.
President McKinley, during his term of office, increased the number of forest reserves from 28 to over 40, covering a total area of 30,000,000 acres. President Roosevelt added many millions of acres to the forest reserves, bringing the net total to more than 150,000,000 acres, including 159 different forests. In 1905, the administration of the forest reserves was transferred from the Department of the Interior to the Department of Agriculture, and their name changed to National Forests. No great additions to the government timberlands have been made since that time. Small, valuable areas have been added. Other undesirable tracts have been cut off from the original reserves.
The growth of the Division of Forestry, now the United States Forest Service, has been very remarkable since 1898, when it consisted of only a few scientific workers and clerks. At present it employs more than 2,600 workers, which number is increased during the dangerous fire season to from 4,000 to 5,000 employees. The annual appropriations have been increased from $28,500 to approximately $6,500,000. The annual income from Uncle Sam's woodlands is also on the gain and now amounts to about $5,000,000 yearly. This income results largely from the sale of timber and the grazing of livestock on the National Forests.
OUR NATIONAL FORESTS
Our National Forests include 147 distinct and separate bodies of timber in twenty-seven different states and in Alaska and Porto Rico. They cover more than 156,000,000 acres. If they could be massed together in one huge area like the state of Texas, it would make easier the task of handling the forests and fighting fires. The United States Forest Service, which has charge of their management and protection, is one of the largest and most efficient organizations of its kind in the world. It employs expert foresters, scientists, rangers and clerks.
The business of running the forest is centred in eight district offices located in different parts of the country with a general headquarters at Washington, D.C. These districts are in charge of district foresters and their assistants.
The district headquarters and the States that they look after are:
No. 1. Northern District, Missoula, Montana. (Montana, northeastern Washington, northern Idaho, and northwestern South Dakota.)
No. 2. Rocky Mountain District, Denver, Colorado. (Colorado, Wyoming, the remainder of South Dakota, Nebraska, northern Michigan, and northern Minnesota.)
No. 3. Southwestern District, Albuquerque, New Mexico. (Most of Arizona and New Mexico.)
No. 4. Intermountain District, Ogden, Utah. (Utah, southern Idaho, western Wyoming, eastern and central Nevada, and northwestern Arizona.)
No. 5. California District, San Francisco, California. (California and southwestern Nevada.)
No. 6. North Pacific District, Portland, Oregon. (Washington and Oregon.)
No. 7. Eastern District, Washington, D.C. (Arkansas, Alabama, Florida, Oklahoma, North Carolina, South Carolina, Georgia, Tennessee, Virginia, West Virginia, New Hampshire, Maine, and Porto Rico.)
No. 8. Alaska District, Juneau, Alaska. (Alaska.)
Each of the National Forests is under the direct supervision of a forest supervisor and is split up into from 5 to 10 or more ranger districts. Each ranger district is in charge of a forest ranger who has an area of from 100,000 to 200,000 acres in his charge.
The National Forests are, for the most part, located in the mountainous region of the West, with small scattered areas in the Lake States, and the White Mountains, Southern Appalachians and Ozarks of the Eastern and Southern States. Many of them are a wilderness of dense timber. It is a huge task to protect these forests against the ravages of fire. Fire fighting takes precedence over all other work in the National Forests. Lookout stations are established on high points to watch for signs of fire. Airplanes are used on fire patrol over great areas of forest. Where railroads pass through the National Forests, rangers operate motor cars and hand-cars over the tracks in their patrol work. Launches are used in Alaska and on some of the forests where there are large lakes, to enable the fire fighters and forest guardians to cover their beats quickly. Every year the National Forests are being improved and made more accessible by the building of permanent roads, trails and telephone lines. Special trails are built to and in the fire protection areas of remote sections. A network of good roads is constructed in every forest to improve fire fighting activities as well as to afford better means of communication between towns, settlements and farms. The road and trail plan followed in the National Forests is mapped out years in advance. In the more remote sections, trails are first constructed. Later, these trails may be developed into wagon or motor roads. Congress annually appropriates large sums of money for the building of roads in the National Forests. Over 25,000 miles of roads and 35,000 miles of trails have already been constructed in these forests.
Communication throughout the National Forests is had by the use of the telephone and the radio or wireless telephone. Signalling by means of the heliograph is practiced on bright days in regions that have no telephones. Arrangements made with private telephone companies permit the forest officers to use their lines. The efficient communication systems aid in the administration of the forests and speeds the work of gathering fire fighters quickly at the points where smoke is detected.
Agricultural and forestry experts have surveyed the lands in the National Forests. Thus they have prevented the use of lands for forestry purposes which are better adapted for farming. Since 1910, more than 26,500,000 acres of lands have been excluded from the forests. These lands were more useful for farming or grazing than for forestry. Practically all lands within the National Forests have now been examined and classified. At intervals Congress has combined several areas of forest lands into single tracts. Government lands outside the National Forests have also been traded for state or private lands within their boundaries. Thus the forests have been lined-up in more compact bodies. Careful surveys are made before such trades are closed to make sure that the land given to Uncle Sam is valuable for timber production and the protection of stream flow, and that the Government receives full value for the land that is exchanged.
The National Forests contain nearly five hundred billion board feet of merchantable timber. This is 23 per cent. of the remaining timber in the country. Whenever the trees in the forest reach maturity they are sold and put to use. All green trees to be cut are selected by qualified forest officers and blazed and marked with a "U.S." This marking is done carefully so as to protect the forest and insure a future crop of trees on the area. Timber is furnished at low rates to local farmers, settlers, and stockmen for use in making improvements. Much fire wood and dead and down timber also is given away. The removal of such material lessens the fire danger in the forest.
Over a billion feet of timber, valued at more than $3,000,000, is sold annually from the National Forests.
One generally does not think of meat, leather and wool as forest crops. Nevertheless, the National Forests play an important part in the western livestock industry. Experts report that over one-fifth of the cattle and one-half of the sheep of the western states are grazed in the National Forests. These livestock are estimated to be worth nearly one-quarter billion dollars. More than 9,500,000 head of livestock are pastured annually under permit in the Federal forests. In addition, some 4,000,000 to 6,000,000 calves and lambs are grazed free of charge.
The ranges suitable for stock grazing are used to pasture sheep, cattle, horses, hogs and goats. The Secretary of Agriculture decides what number and what kind of animals shall graze on each forest. He regulates the grazing and prevents injury to the ranges from being overstocked with too many cattle and sheep. The forest ranges are divided into grazing units. Generally, the cattle and horses are grazed in the valleys and on the lower slopes of the mountain. The sheep and goats are pastured on the high mountain sides and in the grassy meadows at or above timberline.
Preferences to graze live stock on the forest ranges are for the most part granted to stockmen who own improved ranch property and live in or near one of the National Forests. The fee for grazing on forest ranges is based on a yearlong rate of $1.20 a head of cattle, $1.50 for horses, $.90 for hogs and $.30 a head for sheep.
At times it is necessary, for short periods, to prohibit grazing on the Government forest ranges. For example, when mature timber has been cut from certain areas, it is essential that sheep be kept off such tracts until the young growth has made a good start in natural reforestation. Camping grounds needed for recreation purposes by the public are excluded from the grazing range. If a shortage of the water supply of a neighboring town or city threatens, or if floods or erosion become serious due to fire or overgrazing of the land, the range is closed to live-stock and allowed to recuperate. Where artificial planting is practiced, grazing is often forbidden until the young trees get a good start.
The total receipts which Uncle Sam collects from the 30,000 or more stockmen who graze their cattle and sheep on the National Forests amount to nearly $2,500,000 annually. As a result of the teachings of the Forest Service, the stockmen are now raising better livestock. Improved breeding animals are kept in the herds and flocks. Many of the fat stock now go directly from the range to the market. Formerly, most of the animals had to be fed on corn and grain in some of the Middle Western States to flesh them for market. Experiments have been carried on which have shown the advantages of new feeding and herding methods. The ranchers have banded together in livestock associations, which cooeperate with the Forest Service in managing the forest ranges.
It costs about $5 to sow one acre of ground to tree seed, and approximately $10 an acre to set out seedling trees. The seed is obtained from the same locality where it is to be planted. In many instances, cones are purchased from settlers who make a business of gathering them. The Federal foresters dry these cones in the sun and thresh out the seed, which they then fan and clean. If it is desired to store supplies of tree seed from year to year it is kept in sacks or jars, in a cool, dry place, protected from rats and mice. Where seed is sown directly on the ground, poison bait must be scattered over the area in order to destroy the gophers, mice and chipmunks which otherwise would eat the seed. Sowing seed broadcast on unprepared land has usually failed unless the soil and weather conditions were just right. For the most part, setting out nursery seedlings has given better results than direct seeding. Two men can set out between five hundred and one thousand trees a day.
The National Forests contain about one million acres of denuded forest lands. Much of this was cut-over and so severely burned before the creation of the forests that it bears no tree growth. Some of these lands will reseed themselves naturally while other areas have to be seeded or planted by hand. In this way the lands that will produce profitable trees are fitted to support forest cover. Because the soils and climate of our National Forests are different, special experiments have been carried on in different places to decide the best practices to follow. Two method of reforestation are commonly practiced. In some places, the tree seed is sown directly upon the ground and, thereafter, may or may not be cultivated. This method is limited to the localities where the soil and moisture conditions are favorable for rapid growth. Under the other plan, the seedlings are grown in nurseries for several years under favorable conditions. They are then moved to the field and set out in permanent plantations.
THE NATIONAL FORESTS OF ALASKA
There are two great National Forests in Alaska. They cover 20,579,740 acres or about 5-1/2 per cent. of the total area of Alaska. The larger of these woodlands, the Tongass National Forest, is estimated to contain 70,000,000,000 board feet of timber ripe for marketing. Stands of 100,000 board feet per acre are not infrequent. This is the Alaskan forest that will some day be shipping large amounts of timber to the States. It has over 12,000 miles of shore line and ninety per cent. of the usable timber is within two miles of tidewater. This makes it easy to log the timber and load the lumber directly from the forests to the steamers. This forest is 1500 miles closer to the mainland markets than is the other Alaskan National Forest.
In most of the National Forests the rangers ride around their beats on horseback. The foresters in the Tongass use motor boats. They travel in couples; two men to a 35-foot boat, which is provided with comfortable eating and sleeping quarters. The rangers live on the boat all the time. During the summer they work sixteen to twenty hours daily. The days are long and the nights short, and they must travel long distances between points of work. On such runs one man steers the boat and watches the forested shoreline for three or four hours at a time, while his mate reads or sleeps; then they change off. In this way, they are able to make the most efficient use of the long periods of daylight.