PHYSICAL, ECONOMIC, AND SOCIAL 385 



imports annually from 39.5 to 42.5 million dollars worth. Plant new stands with the 

 utmost ardor, since the operation is profitable.^ The pineries, for example, yield 

 5 to 10 per cent. There does not exist any other more advantageous investment. 

 Forestation enriches the planter and makes our country stronger. 



" Social Role — Climate. — Following excessive deforestation, the local climate be- 

 comes worse. The prosperity of agriculture, the health of inhabitants, the pubhc 

 fortune itself, depends upon normal proportion of forest. This per cent is itself an 

 element to regulate the world's circulation of cloud, rain, snow, flood, and even the 

 ocean. The denuded zones in the mountains must be restocked in order to re-establish 

 order in nature, without which all economics are profoundly upset; it is partly due 

 to the absence of forests that one must attribute the burning climate of the interior of 

 Asia, Africa, and Australia. The destruction of stands has produced disastrous climatic 

 changes in Greece, in Russia, ... in Asia Minor, and in certain regions of India. 

 All history agrees on this point. It shows clearly the disastrous effects of great de- 

 forestation on climate. Aristotle, Pliny, and Strabon predicted to their contemporaries 

 the sterility which would follow deforestation . . . which, in lowering the humidity 

 necessary for vegetation, . . . has brought on something more terrible than any 

 war, namely, the decadence of the most powerful empires, . . . those great coun- 

 tries which were the founders of the human race — Mesopotamia, Turkestan, Bactres, 

 the splendor of the Greek civilization under Alexander the Great, Palestine, Syria, 

 deprived of forests made the water, the vegetation, and the inhabitants disappear. 

 Desert and sterile, the jaded country once so populous, deforestation has driven away 

 life itself. Deforestation has even permitted the sea to recover land once cultivated — 

 the Pomeranian shore, the Zuyder Zee. At the middle of the seventeenth century, the 

 Chinese had transformed Tartary into a desert by removing the trees which protected 

 it. Because of deforestation, the temperature of the winter season is even lower than 

 it was in Norway. On the plateau of Iran, the temperature passes in several hours 

 from 60° C. to 7° C. (140° to 44.6° F.). The air is so dry that nothing can withstand 

 it. We must go back to the old tradition and reaUze that it is a scientific fact that the 

 ancient veneration for trees shown by oiu- fathers is because the forest is completely 

 indispensable to creation. 



" Hygiene. — Under the majority of cases, hygiene is intimately linked with forests. 

 From the Roman times it has been recognized that the excessive felling of forests exerts 

 an unfortunate effect upon the physical condition of the country and compromises 

 the health of the inhabitants. Swamp fevers follow deforestation everywhere in the 

 subtropical zones. On the other hand, forestation accompanied by drainage dries up 

 the marshes and diminishes sickness in fever regions such as the Roman Campagna 

 certain steppes of Russia, Tuscan Maremme, in the Landes, in Poitou, and in other 

 places less known. The difference between sickness and health, between prosperity 

 and extreme misery, coincides with the appearance or disappearance of the arborescent 

 mantle. Such are the contemporary facts. The Belgians celebrate by an official 

 fiesta the social role of silviculture, proclaiming that the forests exercise the most healthy 

 influence on chmate and public hygiene. It is not necessary to have great areas of 

 forest to manifest its curative strength. A single eucalyptus tree may drain the excess 

 water from one-quarter of an acre. In Algeria, a hedge several yards in length . . . 

 may guarantee aU the occupants of a house against swamp wet soils so conducive to 

 malaria. Thousands of examples prove it. The marsh of Bonfarick, one of the un- 

 healthiest locaHties in Algeria, has been transformed by planting into one of the health- 

 iest colonies in France. In 30 years the pineries have made healthy, fertile, and rich 



2 This, of course, is an exceptional instance of profitable private forestry. Here worth- 

 less sand wastes were made to yield a handsome revenue (see p. 183). 



