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George Perkins Marsh
American Conservationist
1801-1882 A selection from
THE EARTH AS MODIFIED BY HUMAN ACTION
Narrated by Bruce Miles
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Primitive man had little occasion to fell trees for fuel, or for the
construction of dwellings, boats, and the implements of his rude
agriculture and handicrafts. Windfalls would furnish a thin population
with a sufficient supply of such material, and if occasionally a growing
tree was cut, the injury to the forest would be too insignificant to be
at all appreciable.
The accidental escape and spread of fire or possibly, the combustion of
forests by lightning, must have first suggested the advantages to be
derived from the removal of too abundant and extensive woods, and at the
same time, have pointed out a means by which a large tract of surface
could readily be cleared of much of this natural incumbrance. As soon as
agriculture had commenced at all, it would be observed that the growth
of cultivated plants, as well as of many species of wild vegetation, was
particularly rapid and luxuriant on soils which had been burned over,
and thus a new stimulus would be given to the practice of destroying the
woods by fire, as a means of both extending the open grounds, and making
the acquisition of a yet more productive soil. After a few harvests had
exhausted the first rank fertility of this virgin mould, or when weeds
and briers and the sprouting roots of the trees had begun to choke the
crops of the half-subdued soil, the ground would be abandoned for new
fields won from the forest by the same means, and the deserted plain or
hillock would soon clothe itself anew with shrubs and trees, to be again
subjected to the same destructive process, and again surrendered to the
restorative powers of vegetable nature. In many parts of the
North American States, the first white settlers found extensive tracts
of thin woods, of a very park-like character, called "oak-openings,"
from the predominance of different species of that tree upon them. These
were the semi-artificial pasture-grounds of the Indians, brought into
that state, and so kept, by partial clearing, and by the annual burning
of the grass. The object of this operation was to attract the deer to
the fresh herbage which sprang up after the fire. The oaks bore the
annual scorching at least for a certain time; but if it had been
indefinitely continued, they would very probably have been destroyed at
last. The soil would have then been much in the prairie condition, and
would have needed nothing but grazing for a long succession of years to
make the resemblance perfect. That the annual fires alone occasioned the
peculiar character of the oak-openings, is proved by the fact that as
soon as the Indians had left the country, young trees of many species
sprang up and grew luxuriantly upon them. This rude
economy would be continued for generations, and, wasteful as it is, is
still largely pursued in Northern Sweden, Swedish Lapland, and sometimes
even in France and the United States. The practice of burning
over woodland, at once to clear and manure the ground, is called in
Swedieh svedjande, a participial noun from the verb att svedja, to burn
over. Though used in Sweden as a preparation for crops of rye or other
grain, it is employed in Lapland more frequently to secure an abundant
growth of pasturage, which follows in two or three years after the fire;
and it is sometimes resorted to as a mode of driving the Laplanders and
their reindeer from the vicinity of the Swedish backwoodsman's
grass-grounds and hay-stacks, to which they are dangerous neighbors. The
forest, indeed, rapidly recovers itself, but it is a generation or more
before the reindeer-moss grows again. When the forest consists of pine,
tall, the ground, instead of being rendered fertile by this process,
becomes hopelessly barren, and for a long time afterwards produces
nothing but weeds and briers.
The needs of agriculture are the most familiar cause of the destruction
of the forest in new countries; for not only does an increasing
population demand additional acres to grow the vegetables which feed it
and its domestic animals, but the slovenly husbandry of the border
settler soon exhausts the luxuriance of his first fields, and compels
him to remove his household gods to a fresher soil. The extent of
cleared ground required for agricultural use depends very much on the
number and kinds of the cattle bred.
In the United States, the domestic quadrupeds amount to more than
a hundred millions, or nearly three times the number of the human
population of the Union. In many of the Western States, the swine
subsist more or less on acorns, nuts, and other products of the woods,
and the prairies, or natural meadows of the Mississippi valley, yield a
large amount of food for beast, as well as for man. With these
exceptions, all this vast army of quadrupeds is fed wholly on grass,
grain, pulse, and roots grown on soil reclaimed from the forest by
European settlers. It is true that the flesh of domestic quadrupeds
enters very largely into the aliment of the American people, and greatly
reduces the quantity of vegetable nutriment which they would otherwise
consume, so that a smaller amount of agricultural product is required
for immediate human food, and, of course, a smaller extent of cleared
land is needed for the growth of that product, than if no domestic
animals existed. But the flesh of the horse, the ass, and the mule is
not consumed by man, and the sheep is reared rather for its fleece than
for food. Besides this, the ground required to produce the grass and
grain consumed in rearing and fattening a grazing quadruped, would yield
a far larger amount of nutriment, if devoted to the growing of
breadstuffs, than is furnished by his flesh; and, upon the whole,
whatever advantages may be reaped from the breeding of domestic cattle,
it is plain that the cleared land devoted to their sustenance in the
originally wooded part of the United States, after deducting a quantity
sufficient to produce an amount of aliment equal to their flesh, still
greatly exceeds that cultivated for vegetables, directly consumed by the
people of the same regions; or, to express a nearly equivalent idea in
other words, the meadow and the pasture, taken together, much exceed the
ploughland. The two ideas expressed in the text are not
exactly equivalent, because, though the consumption of animal food
diminishes the amount of vegetable aliment required for human use, yet
the animals themselves consume a great quantity of grain and roots grown
on ground ploughed and cultivated as regularly and as laboriously as any
other.
The 280,000,000 bushels of oats raised in the United States in 1870, and
fed to the 7,000,000 horses, the potatoes, the turnips, and the maize
employed in fattening the oxen, the sheep, and the swine slaughtered the
same year, occupied an extent of ground which, cultivated by hand-labor
and with Chinese industry and skill, would probably have produced a
quantity of vegetable food equal in alimentary power to the flesh of the
quadrupeds killed for domestic use. Hence, so far as the naked question
of AMOUNT of aliment is concerned, the meadows and the pastures might as
well have remained in the forest condition. It must, however, be borne
in mind that animal labor, if not a necessary, is probably an
economical, force in agricultural occupations, and that without animal
manure many branches of husbandry could hardly be carried on at all. At
the same time, the introduction of machinery into rural industry, and of
artificial, mineral, and fossil manures, is working great revolutions,
and we may find at some future day that the ox is no longer necessary as
a help to the farmer.
Governments and military commanders have at different periods
deliberately destroyed forests by fire or the axe, because they afforded
a retreat to robbers, outlaws, or enemies, and this was one of the
hostile measures practised by both Julius Caesar and the Gauls in the
Roman war of conquest against that people. It was also resorted to in
the Mediterranean provinces of France, then much infested by robbers and
deserters, as late as the reign of Napoleon I., and is said to have been
employed by the early American colonists in their exterminating wars
with the native Indians. In 1664 the Swedes made an incursion into Jutland and
felled a considerable extent of forest. After they retired, a survey of
the damage was had, and the report is still extant. The number of trees
cut was found to be 120,000.
With increasing population and the development of new industries, come
new drains upon the forest from the many arts for which wood is the
material. The demands of the near and the distant market for this
product excite the cupidity of the hardy forester, and a few years of
that wild industry of which Springer's "Forest Life and Forest Trees" so
vividly depicts the dangers and the triumphs, suffice to rob the most
inaccessible glens of their fairest ornaments. The value of timber
increases with its dimensions in almost geometrical proportion, and the
tallest, most vigorous, and most symmetrical trees fall the first
sacrifice. More information about George Perkins Marsh from Wikipedia
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