FIRE.
It is not commonly realized that forest fires are almost entirely the result of human agency. When cruisers first began to locate claims in this country, practically no regions had been devastated by fire. Now such regions are to be seen everywhere. Altho lightning occasionally sets fire to forests, especially in the Rocky Mountains, the losses from this cause are trifling compared with the total loss.
Fig. 104. Slash, Left in the Woods, and Ready to Catch Fire. U. S. Forest Service.
Opportunities for fire. There are a number of facts that make the forest peculiarly liable to fire. Especially in the fall there are great quantities of inflammable material, such as dry leaves, twigs, and duff lying loose ready for ignition. The bark of some trees, as "paper birch," and the leaves of others, as conifers, are very inflammable. It follows that fires are more common in coniferous than in deciduous forests. After lumbering or windfalls, the accumulated "slash" burns easily and furiously, Fig. 104. Moreover a region once burned over, is particularly liable to burn again, on account of the accumulation of dry trunks and branches. See [Fig. 107].
Long dry seasons and high wind furnish particularly favorable conditions for fire. On the other hand, the wind by changing in direction may extinguish the fire by turning it back upon its track. Indeed the destructive power of fires depends largely upon the wind.
Fig. 105. Forest Fire. U. S. Forest Service.
Causes of fire. Forest fires are due to all sorts of causes, accidental and intentional. Dropped matches, smouldering tobacco, neglected camp fires and brush fires, locomotive sparks, may all be accidental causes that under favorable conditions entail tremendous loss. There is good reason to believe that many forest fires are set intentionally. The fact that grass and berry bushes will soon spring up after a fire, leads sheep men, cattle and pig owners, and berry pickers to set fires. Vast areas are annually burned over in the United States for these reasons. Most fires run only along the surface of the ground, doing little harm to the big timber, and if left alone will even go out of themselves; but if the duff is dry, the fire may smoulder in it a long time, ready to break out into flame when it reaches good fuel or when it is fanned by the wind, Fig. 105. Even these ground fires do incalculable damage to seeds and seedlings, and the safest plan is to put out every fire no matter how small.
Fig. 106. Burned Forest of Engelmann Spruce. Foreground, Lodgepole Pine Coming in. U. S. Forest Service.
Altho it is true that the loss of a forest is not irremediable because vegetation usually begins again at once, Fig. 106, yet the actual damage is almost incalculable. The tract may lie year after year, covered with only worthless weeds and bushes, and if hilly, the region at once begins to be eroded by the rains.
After the fire, may come high winds that blow down the trunks of the trees, preparing material for another fire, Fig. 107.
Fig. 107. Effect of Fire and Wind. Colorado. U. S. Forest Service.
The statistics of the actual annual money loss of the timber burned in the United States are not gathered. In 1880 Professor Sargent collected much information, and in the census of that year (10th Census, Vol. IX) reported 10,000,000 acres burned that year at a value of $25,000,000.
In 1891, the Division of Forestry collected authentic records of 12,000,000 acres burned over in a single year, at an estimated value of $50,000,000.
In the Adironacks in the spring of 1903, an unprecedentedly dry season, fire after fire caused a direct loss of about $3,500,000.
In 1902, a fire on the dividing line between Washington and Oregon destroyed property amounting to $12,000,000. Within comparatively recent years, the Pacific Coast states have lost over $100,000,000 worth of timber by fire alone.
During September, 1908, forest fires raged in Minnesota, Michigan, Wisconsin, Maine, New York and Pennsylvania. The estimates of loss for northern Michigan alone amounted to $40,000,000. For two weeks the loss was set at $1,000,000 a day. The two towns of Hibbing and Chisholm were practically wiped out of existence, and 296 lives were lost.
Certain forest fires have been so gigantic and terrible as to become historic.
One of these is the Miramichi fire of 1825. It began its greatest destruction about one o'clock in the afternoon of October 7th of that year, at a place about sixty miles above the town of Newcastle, on the Miramichi River, in New Brunswick. Before ten o'clock at night it was twenty miles below New Castle. In nine hours it had destroyed a belt of forest eighty miles long and twenty-five miles wide. Over more than two and a half million acres almost every living thing was killed. Even the fish were afterwards found dead in heaps on the river banks. Many buildings and towns were destroyed, one hundred and sixty persons perished, and nearly a thousand head of stock. The loss from the Miramichi fire is estimated at $300,000, not including the value of the timber. (Pinchot, Part 1. p. 79-80.)
Of such calamities, one of the worst that is on record is that known as the Peshtigo fire, which, in 1871, during the same month, October, when Chicago was laid in ashes, devastated the country about the shores of Green Bay in Wisconsin. More than $3,000,000 worth of property was burnt, at least two thousand families of settlers were made homeless, villages were destroyed and over a thousand lives lost. (Bruncken, p. 110.)
The most destructive fire of more recent years was that which started near Hinckley, Minn., September 1, 1894. While the area burned over was less than in some other great fires, the loss of life and property was very heavy. Hinckley and six other towns were destroyed, about 500 lives were lost, more than 2,000 persons were left destitute, and the estimated loss in property of various kinds was $25,000,000. Except for the heroic conduct of locomotive engineers and other railroad men, the loss of life would have been far greater.
This fire was all the more deplorable, because it was wholly unnecessary. For many days before the high wind came and drove it into uncontrollable fury, it was burning slowly close to the town of Hinckley and could have been put out. (Pinchot, Part I, 82-83.)
One of the most remarkable features of these "crown fires," is the rapidity with which they travel. The Miramichi fire traveled nine miles an hour.
To get an idea of the fury of a forest fire, read this description from Bruncken. After describing the steady, slow progress of a duff fire, he proceeds:
But there comes an evening when nobody thinks of going to bed. All day the smoke has become denser and denser, until it is no longer a haze, but a thick yellowish mass of vapor, carrying large particles of sooty cinders, filling one's eyes and nostrils with biting dust, making breathing oppressive. There is no escape from it. Closing windows and doors does not bar it out of the houses; it seems as if it could penetrate solid walls. Everything it touches feels rough, as if covered with fine ashes. The heat is horrible altho no ray of sunshine penetrates the heavy pall of smoke.
In the distance a rumbling, rushing sound is heard. It is the fire roaring in the tree tops on the hill sides, several miles from town. This is no longer a number of small fires, slowly smouldering away to eat up a fallen log; nor little dancing flames running along the dry litter on the ground, trying to creep up the bark of a tree, where the lichens are thick and dry, but presently falling back exhausted. The wind has risen, fanning the flames on all sides, till they leap higher and higher, reaching the lower branches of the standing timber, enveloping the mighty boles of cork pine in a sheet of flame, seizing the tall poles of young trees and converting them into blazing beacons that herald the approach of destruction. Fiercer and fiercer blows the wind, generated by the fire itself as it sends currents of heated air rushing upward into infinity. Louder and louder the cracking of the branches as the flames seize one after the other, leaping from crown to crown, rising high above the tree tops in whirling wreaths of fire, and belching forth clouds of smoke hundreds of feet still higher. As the heated air rises more and more, rushing along with a sound like that of a thousand foaming mountain torrents, burning brands are carried along, whirling on across the firmament like evil spirits of destruction, bearing the fire miles away from its origin, then falling among the dry brush heaps of windfall or slashing, and starting another fire to burn as fiercely as the first. * * *
There is something horrible in the slow, steady approach of a top fire. It comes on with the pitiless determination of unavoidable destiny, not faster than a man can walk. But there is no stopping it. You cannot fight a fire that seizes tree top after tree top, far above your reach, and showers down upon the pigmy mortals that attempt to oppose it an avalanch of burning branches, driving them away to escape the torture and death that threatens them. (Bruncken, American Forests and Forestry, 106-109.)
Fig. 108. Fighting Forest Fire. U. S. Forest Service.
Real forest fires are not usually put out; men only try to limit them. A common method of limitation is to cut trenches thru the duff so that the fire cannot pass across, Fig. 108. In serious cases back fires are built on the side of the paths or roads or trenches toward the fire, in the expectation that the two fires will meet. In such cases great care has to be taken that the back fire itself does not escape. Small fires, however, can sometimes be beaten out or smothered with dirt and sand, since water is usually unavailable.
Fig. 109. Fire Lane. Worcester Co., Mass. U. S. Forest Service.
But "an ounce of prevention is worth a pound of cure." One of the best of these preventions is a system of fire lanes. Even narrow paths of dirt will stop an ordinary fire. Roads, of course, are still better. Systems of fire lanes, Fig. 109, are made great use of in Europe and British India. Belts of hardwood trees are also cultivated along railways, and to break up large bodies of conifers.
If in lumbering, the slash were destroyed or even cut up so as to lie near the ground and rot quickly, many fires would be prevented.
Some states, as New York, have a fairly well organized system of fire wardens, who have the authority to draft as much male help as they need at $2.00 a day to fight forest fires. Unfortunately "ne'er-do-wells" sometimes set fire to the woods, in order to "make work" for themselves. Much preventive work is also done by educating the public in schools and by the posting of the fire notices,[1] Fig. 110.
Fig. 110. Look out for Fire. Rules and Laws.