Wind's Impact on Forest Growth

immbers of old trees, their removal is usually followed by a vigorous young growth where the old trees stood. In this way the wind helps to keep the forest full of young and healthy trees. But it also breaks and l)lows down great numbers of useful growing members of the forest (tig. 26). Much of this windfall occurs among shallow-rooted trees, or where tlie ground is .soft l�ecause soaked with water, or where the trees have been weakened })y unsoundness or tire. Some storms are strong enough to break the trees they can not overthrow. Damage from wind is not unconnnon in many parts of the United States, and in places the lo.ss from it is very serious. Near the town of High Springs, in Alachua County, Fla., for example, in a region very subject to storms, there is a tract of many square miles, once covered with 3'.) Longleaf Pino, oror which practically all the troos wore killed l>y a great storm several years ago. Some were thrown Hat. some were so racked and so hroken in the top that they died, and very many were diail 111 Uie ulyuiiJii: purest Ucscrvi;, WaaluiigLuu. snapped oti' 15 to 30 feet above the ground. There is little nse in taking precautions against such great calamities, yet the loss from windfall may be very much reduced liy judicious cutting. An unbroken forest is least exposed. 40 SNOW IN THE FOREST. 8now often loads down, l)reaks, and cni.sbo.s tall j-oiui','- trees (tig. 27), especially if wet snow falls heavily before the broadleaf trees have shed their foliaye in tlie fall. Such injury is difficult to guard against. -A young siiruci; luadrd will hut it is well to know tiiat very slim, tall trees suffer more than those whose growth in diameter and height have kept better pace with each other. In many regions snow is so us(>ful in protecting the soil and the young trees that the lianu it docs is (juitc ovcrlialanced by its benefits. 41 FOREST FIRES. Of all the foes which attack the \V(^()cl lands of Nortli America no otlici- is so tcrrihle as fire. Forest tires sprinjij from many different causes. They are often kindled along railroads by sparks from the locomotives. Carelessness is responsible for many tires. Settlers and farmers clearing land or Vmrning grass and brush often allow the fii'e t<} escape into the wt^ods. Someone may drop a half-})urned match or tiie glowing tobacco of a pipe or cigar, or a huntei- or prospector may neglect to extinguish his camp tire, or may build it where it will buri-iiw into t!ic Ihit'k dulf far beyond his i-eaeh. to sniuliler for days, or sll r tt u,, tubs t liiL kllltd \ rii ol I td 1 r iui o ii dt 1 bj joun,, till I r and Western Heml I Olvmi W 1 r tl cr\ ushint,t n 1 ut I 1 weeks, and perhaps to l)reak out as a destructive fire long after he is gone. Many lires are set for malice or revenge, and the forest is often burned over by huckleberry pickers to increa.se the next season's <;rowth of berries, or by the owners of cattle or sheep to make better pasture for their herds. Fire sometimes renews an old forest by killing the veterans and so permitting vigorous young trees to take their place (tig. 'Jo). There is danger from forest tires in the dry portions of the spring and summer, but those w'hich do most harm usuallj- occur in the fall. At whatever time of the year they appear, their destructive power {lepends very nuich on the wind. They can not travel against it except 42 when burning up hill, and not even then if the wind is strong. The wind may give them .strength and .speed 1)y driving them swiftly through unburned, infiummaljle forests, or it may extinguish the iiercest hre in a short time by turning it back over its path, whei-e there is nothing left to burn. Tii lighting forest fire.s the wind is always the first thing to eonsidi-r, and it.s direction must l)e carefully A watched. sudden change of wind maj^ check a lire, or may turn it oflf in a new direction and perhaps threaten the li\es of the men at work by driving it suddenly down upon them. HISTORIC FOREST FIRES. When all the conditions arc favoralile, forest tires sometimes reach gigantic proportions. A few such fires have attained historic impor- tance. One of the.se is the Miramichi fire of 1825. It began its greatest destruction about 1 o'clock in the afternoon of October 7 at a place about 60 niih's above the town of Newcastle, on the Miramichi River in New Brunswick. Before 10 o'ldock at night it was 20 miles below Newcastle. In nine hours it had destroyed a Itelt of forest 80 miles long and 25 miles wide. Over more than two and a half million acres almo.st every living thing Avas killed. Even the fish were after- wards found dead in heaps along the river banks. Fi\e hundred and ninetv buildings were burned, and a number of towns, including Newcastle, Chatham, and Douglastown, were destroyed. One hundred and sixty persons pei'ished and nearly a thou.sand head of stock. The loss from the Miramichi fire is estimated at !?30o.(t(i(�. not liicludiMg the value of the tim))er. In the majority of such forest fires as this the destruction of the timber is a more serious loss by far than that of the cattle and build- ings, for it carries with it the impoverishment of a whole region for tens or even hundreds of years afterwards. The loss of the s(um})age value of the timber at the time of the fire is but a small part of the damage to the neighborhood. The wages that would have been caiiied in limibering, added to the value of the produce that would h;ive been purchased to supply the lumber camps, and the taxes that would have been devoted to roads and other jjublic improvements, furnish a uuich truer measure of how nuu-h, sooner or latei-, it costs a region w lieu its forests are destroyed by fiiv. The Peshtigo fire of October. Is71. was still more severe than the Miramichi. It covered an artni of o('i' 2,(�00 square miles in W'iscon sin, and involved a loss, in timber and other property, of many mil- lions of dollars. Between 1.200 and 1,500 persons perished, including nearly half the population of Peshtigo, at that time a town of 2,00C inhabitants. Other fires of about the same time were most destructive A in Michigan. strip about -tO miles wide and ISO miles long, extending across the central part <jf the Stiite from Lake Michigan to Lake 1 luron,^ 4S was devastatod. The estimated loss in tinibei-was a)M)iit 4,000.0(10, 000 feet board measure and in money over �10.(�00.()(MI. Sev(M-al imndred persons perished. In the early part of Septeiuher, issl, great tires eovered more tiian 1,800 square miles in various parts of Michigan. The estimated loss in property, in addition to many hundred thousand acres of valuable timber, was more than $2,800,0o0. Over .5.000 persons were made destitute, and the number of lixes lost is variously estimated at from 1.50 to 500. The most destructive tire of more recent years was tiiat which started near Hinckley, Minn., September 1, 1894. While the area burned over was less than in some other g-reat tires, the loss of life and property was xery 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 hav'e been far greater. This tire was all the more deplorable because it was wholly unnecessary. For many days l)efore the high wind came and drove it into uncontrollable fury it was ])urning slowly close to the town of Hinckley and could have l)een put out. MEANS OF DEFENSE. The means of fighting forest tires are not everywhere the .same, for they burn in many ditlerent ways; but in every case the best time to A right a tire is at the beginning, before it has had time to spread. delay of even a verj- few minutes may permit a tire that at tirst could easily have l)eeu extinguished to gather headway and get altogether beyond control. When tliere is but a thin covering of leaves and other waste on the ground a tire usually can not burn very hotly or move with much speed. The tires in most hardwood forests are of this kind. They seldom kill large trees, but they destroy seedlings and saplings and kill the bark of older trees in places near the ground. The hollows at the foot of old Chestnuts and other large trees are often the result of these hres. which occur again and again, and so enlarge the wounds instead of allowing them to heal. Moderate tires also occur in dense coniferous forests when ouly the top of a thick layer of dutf is dry enough to burn. The heat may not be great enough to kill any but the smallest and tenderest .vouug trees, but that does not mean that such tire.s do nt) harm. The future of the forest depends on ju.st such voung growth, and whenever the forest floor, which is so necessary both to the trees and for the water supply, is injured or destroyed by fire, the forest sutlers harm. 44 STTRFACE FIRES. Surface fires (fig. 29) may t>e checked if they are feeble by beating them out with green liranches ov by raking the leaves away from a narrow strip across their course. The best tool for this purpose i.s a four-tined pitchfork oi' a common stable fork. In sandy regions a thin and narrow belt of sand is easilj* and quickly sprinkled over the ground with a shovel, and will check the spread of a weak fire, or even of a comparatively hot one if there is no wind. Dirt or .sand thrown on a liurning lir<' is one of the best of all means for putting it out. . 29.--A surfiioe (ire burning slowly against lliu wind. soutLern N In den.se forests with a heavy forest floor lires arc t)fteii hot enough not onl}' to kill the standing timl)er but to consume the trunks and branches altogether, and even to follow the roots far clown into the ground. In forests of this kind fire spreads easily, creeping along on the surface or through the dufl' or under the bark of rotting fallen trees. In the same way it clim])s dead standing trees and ))reaks out in . bursts of flame high in the air. Dead trees help powerfully to spread a fire, for in high winds loose pieces of their burning bark are carried to almost incredible distances and drop into the dry forest far ahead, while in calm weather they scatter burning fraguients all about them when they fall. (See lig. 30.) 45 GROUND FIRES. When (he dutl' is -ery deep or the .soil jjeaty :i tiro miiy burn l)eneath the surfaces of the ground for weeks or even months, .sometimes showing it.s pre.sence by a little smoke, sometimes without giving anj' sign of life. Even a heavy rain may fail to quench a tiro of this kind, which often breaks out again long after it i.s believed to be entirely extinct. Fires which thus ))ui-n into the ground can sometimes be -- Fig. 30. The effect of repeated fires. Not only the old trees are dead, but the seedlings which succeeded them have perished also. "Western Yellow Pine in the Black Hills Forest Reserve, South Dakota. checked only b}' digging a trench through the layer of decaying wood and other vegetable matter to the mineral .soil beneath. Ground tires usually burn much more .slowly than surface tires, but the}^ are exceptionally long lived and very hard to put out. It is of the first importance to attack .such fire.s quickly before they have had time t(j l)urrow far beneath the surfact^ of the ground. .Surface fires arc u.sually far 173 4H less troublesome, but in eit-hei' case tires which kill the trees are generally repeated again and again until the dead timber is consumed (tio-. 31). ',�:,,- ^ Flii. 31.-- Tlicrc-Piiltof li-fl wiUicnit BACK FIRING. The most dangerous and destructive forest tires are those which run )oth along the ground and in the tops of the trees. When a tire leconios intensely hot on the uiound, it may run up the bark, especially if the tr(>es are conifers, and burn in the crowns. Such lires are the fiercest and mo.st destructive of all. Traveling sometimes faster than a man can run, the}' consume enormous quantities of \aluable timber, burn fences, build- ings, and domestic animals, and endanger or even destroy human lives. -- Fig. 'SI. Setting a back tire on the New a .;irie of roarl. Snntiiern They can be checked only by rain or change of wind, or by meeting some A barrier which they can not pass. liari'ier of this kind is often made by .starling another tire some .listancc ahead of tlic principal one. This back tire, as it is called, must ))e allowed to l>ui-n only against the wind and toward the main tire, so that when the two tires meet both must 47 (TO out for liu-k of fuel. To jii-ovt-tit it from nioving- with tho wind, ii haciv fire .should always Im started t)ii tho windward side of a road (tig. .'W) or a raivcd oi- sanded strip, oi' sonic other line which it can lie kept f I'oni crossing. If it i.s allowed to escape it ma}' become as dangerous as the main fire itself. Back fires are sometimes driven beyond control 1>V a change of wind, l)ut the chief danger from their use is caused by t-i^ '\ h[ --V liri. hue aloug a railroad with two cleared spates separated by a doublt r w il Irees intended to catth the sparks persons who, in excitement or fright, light tlicm at the wrong time or in the wrong iilace. Still, there is no other means of tighting fires so powerful and none so eti'ectivo when rightly used. FIRE LINES. -- Fire lines strips kept free from all inflammable material by burn-- ing or otherwise are ver}- useful in checking small fires and of great value as lines of defense in fighting large ones. They are also very effective in keeping fires out of the woods, as, for example, along railroad tracks (fig. 33). But without men to do the fighting they are of as little u.se against really dangerou.s fires as forts without soldiers against invading armies. iLTM^^"^ ""^ CONGRESS l�Mliih'\mm 48 FARMERS' BULLETINS. ^ ��^ ^^^ 619 thl^^{^i^fi;r^,!f^i:^t;-j;--^ Bulletins avai,a,,l.. fo. distribution, .howin^ nfThl atpaprlyicoaftiAognritcoulatnuy;reS,e^nWaatsohrV,R"Reptp^oTnne^s'elnltfait'r^vie^-o.r^An^i''^^^V�'e*^^i?'"'7:''''"'"' ';.' '^^^n"t' t'o^ ^r.'' ongress, "a"n^y^ ^a'.^k'l^r'^e-s', oS or to the Secre- SlS tinue.1, being superse led bulletins '''"' ""'^''"'"^ '^'^^" ^'"''' discon- 16. 21. Leguminous Plant.s. Barnyard Manure. Pn 24' Pn 32 u 9j' 24. HS^otg?^C?,h'o"ile'r"aS of Farm Animals. and Swine Plague Pp 3Pn to. 27. 28. 29. 30. SGWFPoreleuaaearnpdxiuesntt;ogsDri:AasSnenCeaddueslde(tHsunrnedatFnoidlKi,,UlTslesT,iPli,^,P1 pMliil2r4k|.. 32, SI Alfnlfn, or I ,:r 11-11 m,,lC,,,,l % Pf. I ll. I'n�liirts Pp. 16. ' I's. Pp.12. , "''' ^- :.'."'r,:.'o7. use. Pp. 24. .Milk. Pp.29. '�nl on tlie Farm, pp 20 I'.Tlili/.Ts. T'p.24. ;�? g'^Pei'mPlt station Work-xir. 106. Breeds of Dairy Cattle. Pp. 4s Pp'^' 32 }10n8l.- SIa'l^tPb,u?s"h'e?sTM.' Station Pp. 20 Work-Xlil pp 32 ' 109. Farmers' Reading Courses Pi, �n 110. Rice Culture in th,. r, ,i siatis it, >� 111. 112. 113. 114. 115. Farmers' Interest in (i s 1 ' I Bread and The Apple aBrnedaHd oJwlaktion^G-rowI'ipi'"io Experiment Hop Culture Station Work--XIV. in California. Pp -7 Pn' ^j Pn t) Pn^' 28 116. Irrigation in Fruit Growing. Pp. is ^^''' """^ ^�''"'' '" "'^ Northwest. Pp.'''28 XV 118. Grape Growing in the .South. U9. Experiment Station Work-- Pp ,30 Pn' 31 120. Insects AfTecliiii; Tobacco Pp so * 121. B, 122. I 123. I il: Ii Pi.. :r.' ' "i 1" >l<iriii Crain. Pp.21. "'"i;'i 'iMiiiili'S. Pp.27. 1 - 111' I illi.n Plant. Pp.:i2 ii^.il(..li.,u. Pp.16. <'� I'll. 24. 11 Forage Crop. Pp.20. nftie.sof Chicken.s. Pp.48 ''t. Pp.4S. 130 V .Miislirooms. Pp. 20. "II Hirds. Pp.40. '111. l'p.2I. 57. liii >S. Th .59. H,-, Miili.Mi \V,,rk-I. Pp.31. 1- 11 ilh- Farm. Pp. ic. 1 I 'rage Crop. Pp.24. I 'I'lij,-; I'ohacei Pp. lij 'I'lre. I'p,40. im Produce. Pp.28 "U the Farm. P" p.40, rse. Pp .IX n. Pp.32. ii"..n.-r. 1 Pp.22. ""il. III. Pp..'i2. i'<i.;l,,,., Pp.2.1, '"Incli..n. Pp, 21, .^"1111. west, I>p.:!2, Milk MS Food. \,,rk-IV, Pp.:!.,). Pp,32. The Grain .Smuts. Pp. 20, "6. Tomato ' (; '" Pp',30' 77, TheLiniir I Soils, Pp,l.. 78, Expr-iirin Mii-i, Work-V. Pp, 79, Expi'iii:, 80, The I '.Ml 81, r..rn 11;' Uork-Vl, , P, 1M-, Pp, ],;, II iIl' i'S.uih, Pp,24, 96, Raisin- s 97, Experini. 98, SUTCosti.,1 99, Ii,:-,v, 1-,,, 100, If ! Pp.23. lation Work-VII, Pp, 30, US Plants, Pp..s2, at ion Work-- Vin, Pp, 23. Pp.:!2. Pp. 32, i>, ii; s and Treatment, lion Work--IX Pp, 27. Pp. 12. Pp. 30. harden. Pp, 24, Farmers, Pp, 47. . p 1 "iMutton. Pp.48. uli,,,, Work-X. Pp..32. S'lnth.rn Farmers. Pp.48 -oi Shade Trees. Pp,:w 1 I lie South. Pp.40. Work-X 1]0^3i. y '" ' 'ii.-e Plants. l,,.p.in,,en(,-latlon 104. ^otcSOU Frost. Pp.24. Pp.4,s. r. Pp. ^^ LTBRORy or ^ 002 818'^ig^'^