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, st.u.r.dy 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. Quant.i.ties 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 ma.s.ses 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.
[Ill.u.s.tration: SECTION OF A VIRGIN FOREST]
Diseased trees are a menace to the forest. They rob the healthy trees of s.p.a.ce, 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 s.p.a.ce 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 gra.s.s and debris and thus aids freshets and floods. In the Alps of France sheep grazing destroyed the mountain forests and, later on, the gra.s.s 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 sh.o.r.es 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 pa.s.sed an ordinance prohibiting the cutting of timber from the Colony lands without official consent. This is said to be the first conservation law pa.s.sed 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 pa.s.sed 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 ent.i.tled 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.
[Ill.u.s.tration: CUTTING MATURE TREES AND LEAVING SEED TREES TO INSURE A SECOND CROP]
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.
CHAPTER IX
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 ma.s.sed 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 a.s.sistants.
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.)