Camping among forests quickly gives one a home feeling for them and develops an appreciation2 of their value. How different American history might have been had Columbus discovered a treeless land! The American forests have largely contributed to the development of the country. The first settlers on the Atlantic coast felled and used the waiting trees for home-[Pg 124]building; they also used wood for fuel, furniture, and fortifications. When trading-posts were established in the wilderness3 the axe4 was as essential as the gun. From Atlantic to Pacific the pioneers built their cabins of wood. As the country developed, wood continued to be indispensable; it was used in almost every industry, and to-day it has a more general use than ever.
SPANISH MOSS5 AT LAKE CHARLES, LOUISIANA SPANISH MOSS AT LAKE CHARLES, LOUISIANA
Forests enrich us in many ways. One of these is through the supply of wood which they produce,—which they annually6 produce. Wood is one of the most useful materials used by man. Wood is the home-making material. It gives good cheer to a million hearthstones. How extensively it is used for tools, furniture, and vehicles, for mine timbers and railroad development! The living influences which forests exert, the environments which they create and maintain, are potent7 to enable man best to manage and control the earth, the air, and the water, so that these will give him the greatest service and do him the least damage.
Forests are water-distributors, and everywhere their presence tends to prevent both [Pg 125] floods and extreme low water; they check evaporation8 and assist drainage; they create soil; they resist sudden changes of temperature; they break and temper the winds; they do sanitary9 work by taking impurities10 from the air; they shelter and furnish homes for millions of birds which destroy enormous numbers of weed-seed and injurious insects. Lastly, and possibly most important, forests make this earth comfortable and beautiful. Next to the soil, they are the most useful and helpful of Nature's agencies.
Forests are moderators of climate. They heat and cool slowly. Their slow response to change resists sudden changes, and, consequently, they mitigate11 the rudeness with which sudden changes are always accompanied. Sudden changes of temperature are often annoying and enervating12 to man, and frequently do severe damage to domestic plants and animals. They sometimes have what may be called an explosive effect upon the life-tissues of many plants and animals which man has domesticated13 and is producing for his benefit. Many plants have been domesticated and largely so specialized15 that they have[Pg 126] been rendered less hardy16. With good care, these plants are heavy producers, but, to have from them a premium17 harvest each year, they need the genial18 clime, the stimulating19 shelter, and the constant protection which only forests can supply. Closely allied20 to changes of temperature is the movement of the air. In the sea every peninsula is a breakwater: on land every grove21 is a windbreak. The effect of the violence of high winds on fruited orchards22 and fields of golden grain may be compared to the beatings of innumerable clubs. Hot waves and cold waves come like withering23 breaths of flame and frost to trees and plants. High winds may be mastered by the forest. The forest will make even the Storm King calm, and it will also soften24, temper, and subdue25 the hottest or the coldest waves that blow. Forests may be placed so as to make every field a harbor.
The air is an invisible blotter that is constantly absorbing moisture. Its capacity to evaporate and absorb increases with rapidity of movement. Roughly, six times as much water is evaporated from a place that is swept[Pg 127] by a twenty-five-mile wind as from a place in the dead calm of the forest. The quantity of water evaporated within a forest or in its shelter is many times less than is evaporated from the soil in an exposed situation. This shelter and the consequent decreased evaporation may save a crop in a dry season. During seasons of scanty26 rainfall the crops often fail, probably not because sufficient water has not fallen, but because the thirsty winds have drawn27 from the soil so much moisture that the water-table in the soil is lowered below the reach of the roots of the growing plants.
In the arid28 West the extra-dry winds are insatiable. In many localities their annual capacity to absorb water is greater than the annual precipitation of water. In "dry-farming" localities, the central idea is to save all the water that Nature supplies, to prevent the moisture from evaporating, to protect it from the robber winds. Forests greatly check evaporation, and Professor L. G. Carpenter, the celebrated29 irrigation engineer, says that forests are absolutely necessary for the interests of irrigated30 agricul[Pg 128]ture. Considering the many influences of the forest that are beneficial to agriculture, it would seem as though ideal forest environments would be the best annual assurance that the crops of the field would not fail and that the soil would most generously respond to the seed-sower.
So well is man served in the distribution of the waters and the management of their movements by the forests, that forests seem almost to think. The forest is an eternal mediator31 between winds and gravity in their never-ending struggle for the possession of the waters. The forest seems to try to take the intermittent32 and ever-varying rainfall and send the collected waters in slow and steady stream back to the sea. It has marked success, and one may say it is only to the extent the forest succeeds in doing this that the waters become helpful to man. Possibly they may need assistance in this work. Anyway, so great is the evaporation on the mountains of the West that John Muir says, "Cut down the groves33 and the streams will vanish." Many investigators34 assert that only thirty per cent of the rainfall is returned by the rivers[Pg 129] to the sea. Evaporation—winds—probably carry away the greater portion of the remainder. Afforestation has created springs and streams, not by increasing rainfall, although the forests may do this, but by saving the water that falls,—by checking evaporation. On some exposed watersheds35 the winds carry off as much as ninety per cent of the annual precipitation. It seems plain that wider, better forests would mean deeper, steadier streams. Forests not only check evaporation, but they store water and guard it from the greed of gravity. The forest gets the water into the ground where a brake is put upon the pull of gravity. Forest floors are covered with fluffy37 little rugs and pierced with countless38 tree-roots. So all-absorbing is the porous39, rug-covered forest floor that most of the water that falls in the forest goes into the ground; a small percentage may run off on the surface, but the greater part settles into the earth and seeps40 slowly by subterranean41 drainage, till at last it bubbles out in a spring some distance away and below the place where the raindrops came to earth. The underground[Pg 130] drainage, upon which the forest insists, is much slower and steadier than the surface drainage of a treeless place. The tendency of the forest is to take the water of the widely separated rainy days and dole42 it out daily to the streams. The forest may be described as a large, ever-leaking reservoir.
The forest is so large a reservoir that it rarely overflows43, and seepage44 from it is so slow that it seldom goes dry. The presence of a forest on a watershed36 tends to give the stream which rises thereon its daily supply of water, whether it rains every day or not. By checking evaporation, the forest swells45 the volume of sea-going water in this stream, and thereby46 increases its water-power and makes it more useful as a deep waterway. Forests so regulate stream-flow that if all the watersheds were forested but few floods would occur. Forest-destruction has allowed many a flood to form and foam47 and to ruin a thousand homes. A deforested hillside may, in a single storm, loose the hoarded48 soil of a thousand years. Deforestation may result in filling a river-channel and in stopping boats a thou[Pg 131]sand miles downstream. By bringing forests to our aid, we may almost domesticate14 and control winds and waters!
One of the most important resources is soil,—the cream of the earth, the plant-food of the world. Scientists estimate that it takes nature ten thousand years to create a foot of soil. This heritage of ages, though so valuable and so slowly created, may speedily be washed away and lost. Forests help to anchor it and to hold it in productive places. Every tree stands upon an inverted49 basket of roots and rootlets. Rains may come and rains may go, but these roots hold the soil in place. The soil of forest-covered hillsides is reinforced and anchored with a webwork of the roots and rootlets of the forest. Assisting in the soil-anchorage is the accumulation of twigs50 and leaves, the litter rugs on the forest floor. These cover the soil, and protect it from both wind and water erosion. The roots and rugs not only hold soil, but add to the soil matter by catching51 and holding the trash, silt52, dust, and sediment53 that is blown or washed into the forest. The forest also creates new soil,[Pg 132] enriches the very land it is using. Trash on a forest floor absorbs nitrogenous matter from the air; every fallen leaf is a flake54 of a fertilizer; roots pry55 rocks apart, and this sets up chemical action. Acids given off by tree-roots dissolve even the rocks, and turn these to soil. A tree, unlike most plants, creates more soil than it consumes. In a forest the soil is steadily56 growing richer and deeper.
Birds are one of the resources of the country. They are the protectors, the winged watchmen, of the products which man needs. Birds are hearty57 eaters, and the food which they devour58 consists mostly of noxious59 weed-seed and injurious insects. Several species of birds feed freely upon caterpillars60, moths61, wood-lice, wood-borers, and other deadly tree-enemies. Most species of birds need the forest for shelter, a home, and a breeding-place; and, having the forest, they multiply and fly out into the fields and orchards, and wage a more persistent62 warfare63 even than the farmer upon the insistent64 and innumerable crop-injuring weeds, and also the swarms65 of insatiable crop-devouring insects.[Pg 133] Birds work for us all the time, and board themselves most of the time. Birds are of inestimable value to agriculture, but many of these useful species need forest shelter. So to lose a forest means at the same time to lose the service of these birds.
The forest is a sanitary agent. It is constantly eliminating impurities from the earth and the air. Trees check, sweep, and filter from the air quantities of filthy66, germ-laden dust. Their leaves absorb the poisonous gases from the air. Roots assist in drainage, and absorb impurities from the soil. Roots also give off acids, and these acids, together with the acids released by the fallen, decaying leaves, have a sterilizing67 effect upon the soil. Trees help to keep the earth sweet and clean, and water which comes from a forested watershed is likely to be pure. Many unsanitary areas have been redeemed68 and rendered healthy by tree-planting.
Numerous are the products and the influences of the trees. Many medicines for the sick-room are compounded wholly or in part from the bark, the fruit, the juices, or the leaves of trees.[Pg 134] Fruits and nuts are at least the poetry of the dining-table. One may say of trees what the French physician said of water: needed externally, internally, and eternally! United we stand, but divided we fall, is the history of peoples and forests. Forest-destruction seems to offer the speediest way by which a nation may go into decline or death. "Without forests" are two words that may be written upon the maps of most depopulated lands and declining nations.
When one who is acquainted with both history and natural history reads of a nation that "its forests are destroyed," he naturally pictures the train of evils that inevitably69 follow,—the waste and failure that will come without the presence of forests to prevent. He realizes that the ultimate condition to be expected in this land is a waste of desolate70 distances, arched with a gray, sad sky beneath which a few lonely ruins stand crumbling71 and pathetic in the desert's drifting sand.
The trees are our friends. As an agency for promoting and sustaining the general welfare, the forest stands pre?minent. A nation which[Pg 135] appreciates trees, which maintains sufficient forests, and these in the most serviceable places, may expect to enjoy regularly the richest of harvests; it will be a nation of homes and land that is comfortable, full of hope, and beautiful.
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1
revered
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| v.崇敬，尊崇，敬畏( revere的过去式和过去分词 ) | |
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appreciation
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| n.评价；欣赏；感谢；领会，理解；价格上涨 | |
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wilderness
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| n.杳无人烟的一片陆地、水等，荒漠 | |
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axe
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| n.斧子；v.用斧头砍，削减 | |
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moss
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| n.苔，藓，地衣 | |
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annually
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| adv.一年一次，每年 | |
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potent
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| adj.强有力的，有权势的；有效力的 | |
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evaporation
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| n.蒸发，消失 | |
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sanitary
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| adj.卫生方面的，卫生的，清洁的，卫生的 | |
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impurities
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| 不纯( impurity的名词复数 )； 不洁； 淫秽； 杂质 | |
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mitigate
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| vt.（使）减轻，（使）缓和 | |
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enervating
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| v.使衰弱，使失去活力( enervate的现在分词 ) | |
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domesticated
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| adj.喜欢家庭生活的；（指动物）被驯养了的v.驯化( domesticate的过去式和过去分词 ) | |
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domesticate
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| vt.驯养；使归化，使专注于家务 | |
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specialized
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| adj.专门的，专业化的 | |
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hardy
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| adj.勇敢的，果断的，吃苦的；耐寒的 | |
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premium
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| n.加付款；赠品；adj.高级的；售价高的 | |
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genial
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| adj.亲切的，和蔼的，愉快的，脾气好的 | |
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stimulating
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| adj.有启发性的，能激发人思考的 | |
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allied
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| adj.协约国的；同盟国的 | |
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grove
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| n.林子，小树林，园林 | |
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orchards
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| （通常指围起来的）果园( orchard的名词复数 ) | |
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withering
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| 使人畏缩的，使人害羞的，使人难堪的 | |
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soften
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| v.(使)变柔软；(使)变柔和 | |
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subdue
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| vt.制服，使顺从，征服；抑制，克制 | |
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scanty
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| adj.缺乏的，仅有的，节省的，狭小的，不够的 | |
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drawn
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| v.拖，拉，拔出；adj.憔悴的，紧张的 | |
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arid
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| adj.干旱的；(土地)贫瘠的 | |
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celebrated
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| adj.有名的，声誉卓著的 | |
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irrigated
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| [医]冲洗的 | |
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mediator
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| n.调解人，中介人 | |
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intermittent
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| adj.间歇的，断断续续的 | |
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groves
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| 树丛，小树林( grove的名词复数 ) | |
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investigators
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| n.调查者，审查者( investigator的名词复数 ) | |
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35
watersheds
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| n.分水岭( watershed的名词复数 )；分水线；转折点；流域 | |
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watershed
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| n.转折点，分水岭，分界线 | |
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fluffy
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| adj.有绒毛的，空洞的 | |
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countless
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| adj.无数的，多得不计其数的 | |
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porous
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| adj.可渗透的，多孔的 | |
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seeps
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| n.（液体）渗( seep的名词复数 )；渗透；渗出；漏出v.（液体）渗( seep的第三人称单数 )；渗透；渗出；漏出 | |
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subterranean
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| adj.地下的，地表下的 | |
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42
dole
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| n.救济，（失业）救济金；vt.（out）发放，发给 | |
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43
overflows
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| v.溢出，淹没( overflow的第三人称单数 )；充满；挤满了人；扩展出界，过度延伸 | |
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seepage
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| n.泄漏 | |
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45
swells
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| 增强( swell的第三人称单数 )； 肿胀； （使）凸出； 充满（激情） | |
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46
thereby
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| adv.因此，从而 | |
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foam
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| v./n.泡沫，起泡沫 | |
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48
hoarded
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| v.积蓄并储藏（某物）( hoard的过去式和过去分词 ) | |
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49
inverted
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| adj.反向的，倒转的v.使倒置，使反转( invert的过去式和过去分词 ) | |
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50
twigs
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| 细枝，嫩枝( twig的名词复数 ) | |
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51
catching
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| adj.易传染的，有魅力的，迷人的，接住 | |
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52
silt
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| n.淤泥，淤沙，粉砂层，泥沙层；vt.使淤塞；vi.被淤塞 | |
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53
sediment
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| n.沉淀，沉渣，沉积(物) | |
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54
flake
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| v.使成薄片；雪片般落下；n.薄片 | |
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55
pry
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| vi.窥(刺)探，打听；vt.撬动(开，起) | |
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56
steadily
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| adv.稳定地；不变地；持续地 | |
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hearty
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| adj.热情友好的；衷心的；尽情的，纵情的 | |
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58
devour
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| v.吞没；贪婪地注视或谛听，贪读；使着迷 | |
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59
noxious
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| adj.有害的，有毒的；使道德败坏的，讨厌的 | |
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60
caterpillars
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| n.毛虫( caterpillar的名词复数 )；履带 | |
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moths
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| n.蛾( moth的名词复数 ) | |
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persistent
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| adj.坚持不懈的，执意的；持续的 | |
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warfare
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| n.战争(状态)；斗争；冲突 | |
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insistent
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| adj.迫切的，坚持的 | |
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swarms
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| 蜂群，一大群( swarm的名词复数 ) | |
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66
filthy
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| adj.卑劣的；恶劣的，肮脏的 | |
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67
sterilizing
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| v.消毒( sterilize的现在分词 )；使无菌；使失去生育能力；使绝育 | |
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68
redeemed
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| adj. 可赎回的，可救赎的 动词redeem的过去式和过去分词形式 | |
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69
inevitably
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| adv.不可避免地；必然发生地 | |
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70
desolate
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| adj.荒凉的，荒芜的；孤独的，凄凉的；v.使荒芜，使孤寂 | |
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crumbling
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| adj.摇摇欲坠的 | |
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