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.
CHAPTER V
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.
CHAPTER VI
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 coöperate 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.
CHAPTER VII
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.
CHAPTER VIII
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.