there are so many little burr oak saplings creeping along up the hill-sides that I marvel how they got there. This oak is strangely typical of the white pioneer of this section. At first there were a few scattering trees of large size along the banks of the streams, where natural protection from fire enabled them to grow and spread their limbs in rugged strength and healthfulness. A few years more, and bushes of the same kind sprouted up in sheltered nooks and dells and about the bases of the bluffs. Before these were so high as a man's head, other germs of oak life broke through the sod further away from the parental stem. And so it went on, until now this sturdy tree promises to possess all uncultivated land, if spared by the ax. Here and there the brown verdure is relieved by a speck of green, denoting the presence of a clump of small cedars, or, mayhap, a patriarch that escaped the prairie fires of aboriginal days. These, sharply defined against the gray bluff or blue sky, and relieved by the brown and leafless arms of the oak or elm, make a dot of landscape that would secure immortality to the artist whose pencil could reproduce it with fidelity to nature."*

A belief is freely expressed that greater proportionate successful tree growing, and at compartively no expense, has been done by nature, than by man planting. As stated before, by far greater proportions such planting and growing stands and succeeds than that of artificial processes. Losses are rare, and only from occasional invading fires, and where too thick on the ground the stronger kill out the weaker-no loss in fact, simply adjusting or equalizing.

Personal knowledge is had, in many instances, where lands twenty and twenty-five years ago were considered worthless, have grown to be valued at from twenty to one hundred dollars per acre, solely for the timber value nature planted and grew.

In conclusion let it be remembered, " Man's conquest over nature is not for a generation, but for all generations. One bequeaths its work to the next. The old builders knew, or rather limitations on them, compelled observance of this law. They attempted not to complete a great work in a single lifetime. They laid foundations broad and strong. They built as though they meant endurance. They did what they could, and left that unfinished to their successors. So the great walls of the masters remain to-day a wonder to the world-solid in fabric and rich in ornamentation." Let these truisms point the way to those who aim to rehabilitate the denuded, or invest naturally treeless domain.

Notwithstanding Dr. Warder was prevented from attending the meeting by the floods in the Ohio river, he has kindly supplied the following paper, which the Secretary deems appropriate to follow the valuable paper by Gov. Furnas on the same topic. Dr. Warder is so well and so favorably known that the Secretary presents this paper without further introduction or apology.

J. D. Calhoun, in State Journal.

INFLUENCE OF FORESTS ON HEALTH.

BY JOHN A. WARDER, M. D.

A medical friend*, who has strenuously advocated the preservation of forests for their hygienic influence, in a recent paper presented before the American Forestry Congress, took for his thesis the following proposition: "Trees conduce to health, and the more trees the more health."

He takes and maintains the position that trees notably modify the climate by arresting the currents of air, the winds, which constitute an important element in climate, the influence of which, he thinks, has been far too much overlooked by writers on hygiene. He asserts that "a windy climate is a bad climate-wind interferes with health as well as comfort; it punishes hearty persons and is ruinous to invalids; it interferes with good ventilation, and with the moderate, uniform warmth that should prevail in our houses. A windy climate is a climate of shivers and snuffles, and colds and consumption. Therefore, I say, the more trees the less wind, the more trees the more health."

He also advocates the effects of forests on the score of temperature. Admitting that the mean average temperature may be the same in wooded as in open regions, he claims that "the annual means have little to do with health. What concerns the physician and the sanitarian most is the extent and the rapidity of the oscillations of temperature; here the influence of forests is eminently conservative." From which the writer will not demur, but proceeds:

CLIMATIC INFLUENCES OF FORESTS.

While it will not be insisted upon that the general rainfall will be increased, as is so generally supposed, the forests do undoubtedly exert an important influence upon the climatic conditions. The general storms of our country may be dependent upon the relative configuration of land and water, as well as upon the lines of elevations. These are conditions that are arranged on a plan of grand proportions. They cover continental areas; still, it may safely be asserted, that the fortunate or judicious distribution of forests in prairie regions, and even on our great western plains, can not fail to exert a controling influence of vast importance and of greater or less extent. Certainly the local climate will be affected by the woodlands, which act upon it in the following manner:

First-By checking the force of the currents of air, woodlands will, in a great measure, prevent excessive evaporation, and the moisture thus permitted to remain in the soil will prove as valuable as an equal amount in rainfall.

Second-The forests are of great value in a similar way by the influence of their shade, which prevents the fierce rays of the sun from exercising an ad*Dan. Milliken, M. D., Hamilton, Ohio.

ditional power in drying the soil by evaporation. This has been fully demonstrated by the long continued experiments of Prof. Ebermeyer, of Bavaria. Third-The trees are of great value by their agency in the same direction through the action of their leaves, which cause a more copious condensation of the atmospheric humidity than will occur in closely adjacent lands bare of such vegetation. This fact has been abundantly proved by the experiments of the same careful observer, whose results have been confirmed by others.

Fourth-It has been found, moreover, that the atmosphere within a forest of some extent is always more humid than that of open lands in the same neighborhood. So also the temperature of the forests and of the soil itself is always lower in summer and higher in winter than that of the open lands, cultivated or waste; the climate is rendered more equable.

Fifth-Another very important matter must be apparent to the most casual observer, to-wit: That the moisture precipitated on forest lands is, in a great measure, retained and allowed to percolate quietly into the loose and mellow soil, and even to reach the subsoil and fissile rocks beneath. Its flow is obstructed by fallen leaves, twigs, branches and logs, by mosses, roots and herbage; whereas, the same amount of rain, when falling upon the compact turf of a grassy pasture or upon the bare surface of arable lands, especially when these are firmly trodden, sun-baked or frozen, will at once flow off by every depression, carrying with it the best elements of the soil, suddenly swelling the streams, and eventually cutting the fields into frightful gullies and chasms so as to destroy their usefulness as farm lands.

Sixth-Most especially is it important to preserve forest growths upon declivitous lands, hillsides and river banks, particularly in those regions where our streams take their source. Mountain regions, emphatically those of an Alpine character, should be largely, nay, almost exclusively devoted to forests, and these should be sacredly preserved, for in this condition alone can such tracts of country most perfectly fulfill the destiny for which they seem to have been designed by an all-wise Creator.

The mountains are the sources of the streams which fructify the earth. They intercept the floating clouds, laden with vapor, that is precipitated upon them; when forested, this is retained and furnishes perennial springs, that combine their many contributions to fill the streams which unite to form the world's rivers, and thus, after enriching the earth and turning the busy wheels of manufactures, they open to us channels of commerce of the most valuable and economical character.

If these elevated regions be chiefly covered with trees, they are in the best possible condition to fulfill their admirable function of receivers and reservoirs of pure and healthful waters, which they slowly, but regularly and faithfully, give up for our use and for the continued fertility of the earth.

EFFECTS OF EXPOSING THE MOUNTAINS.

But it has been again and again demonstrated that where the cupidity of man has ruthlessly destroyed the natural arboreal covering of such regions,

that the perennial and gently flowing rivulet has, at frequent intervals, become the uncontrollable mountain torrent, which, in its rapid course to the lower levels, bears everything before it. It first takes away the accumulated soil, produced by ages of decay, from the action of the elements upon the rocks, and mingled with the moldering remains of vegetation, long since gathered from the atmosphere by nature's chemistry. Then the rocks themselves yield to the impetuous current, the mountain sides are scored and gashed, rent into frightful fissures and canyons, that are filled for a few hours in every storm with a turbid stream laden with the debris which floods the fertile valleys. This spreads ruin among the villages, destroying bridges, roads, houses, cattle and even human beings, while at the same time the once fertile plains and intervales are covered with obnoxious debris and rendered unfit for culture. So terribly have certain portions of Europe suffered from this cause, even in enlightened States, that it has become necessary to meet the evil by government interference, requiring the reforestation of large tracts of such mountains. Already we may see the happy effects of the reboisement of Alpine heights in many of the provinces of France and other countries. The same terrible results are in prospect as a consequence of the ruthless destruction of the timber in the mountain regions of our own Western territories.

SHELTER BELTS.

Even the richest arable lands of our country are found to be very generally enhanced in productiveness by judicious planting of forest trees, arranged as shelter belts. These break the force of the blasts which sweep over any great extent of open country that lies in broad plateaux, unbroken by any considerable line of elevation. This effect is equally marked in summer, the season of growth, as in the period of wintry storms.

This sheltering influence of trees is well understood by the Chinese, with their dense population, and where every rood must maintain its man, for while the whole surface is cultivated with sedulous care, we are told by intelligent travelers that the lines of trees scattered here and there give the impression at some distance that you are in a wooded country.

A somewhat similar appearance is presented in the highly cultivated and densely populous regions of portions of Holland and some other countries, where these wind-breaks have been planted, and are fully appreciated for the shelter they afford.

But we need not look abroad for illustrations of the great value of such plantations. In portions of our own prairie regions there are many intelligent cultivators who have learned the value of such shelter-belts around their farms. Judge C. Whiting, of Monona county, Iowa, asserts that since he has planted and grown such barriers against the winds, he has realized more profit from the crops produced upon the remaining four-fifths of his land than formerly, when it was open prairie, he was able to harvest from the whole farm in the same kind of crops.

PROTECTION TO MEN.

In the western half of Minnesota there is a large tract of very fertile land (10,000,000 acres), said to be capable of becoming the granary of the Northwest, on account of its wonderful adaptation to the wheat crop. This region is estimated to possess but one acre of natural timber to the section (or square mile of 640 acres). Immigration into this region was attempted, but the terrible severity of the winter's winds drove back the distressed settlers, until it was shown, by the successful efforts of Mr. L. B. Hodges, that shelter could be cheaply and quickly furnished by tree planting. This demonstration was followed by a large influx of an industrious population.

But every gardener understands the great benefits he derives from shelter hedges, even where they are kept trimmed down to a moderate height. This is especially the case when these wind-screens are composed of evergreens. Such lines of living plants not only check the driving winds, and thus ward off constant accessions of cold air, but they at the same time prevent, to a certain extent, the increased evaporation that would result, and its attendant depression of temperature. Besides this, the living plants themselves appear to have an amount of specific heat within them, as has been proved by observations made at some of the forest experiment stations in Germany. A series of observations made in the neighborhood of St. Louis, by Mr. Tice, showed the protecting influence exerted by an evergreen hedge which extended for several rods to the leeward, before the thermometers indicated the same degree of cold as those on the windward side. [Mr. Tice's experiments, reported in Ills. Hort. Trans.]

WOODLANDS RETAIN MOISTURE.

But another fact in reference to the influence of forests upon climates and its results is too important to be overlooked. Woodlands are not only receptive of snows and rains, but they are also remarkably retentive of these treasures from the skies. Beneath the trees we usually find the soil loose and open; the surface is more or less covered by the debris of decaying vegetable matter, all of which must receive, absorb and temporarily retain the rains and melting snows until the fluid may quietly settle into the soil and subjacent rocks, and thus the forest regions become reservoirs for supplying springs that pour forth the runlets, rivulets and streams which eventually form the rivers of the continents.

SAND-WASTES-SAND-DUNES.

While considering the relations of forestry, we should not overlook the immense value of tree plantations upon low, sandy lands. These sometimes occur in the interior of a continent, though they are more frequent in situations exposed to the sea, where the combined influence of the waves and the winds pile up the sands into great dunes that are often mercilessly wafted