128 B. Eb. Fernow—The Battle of the Forest. 
conditions of existence in the thousandth that is possessed in 
the hundredth or the tenth year of its age? 
“The old and central part of the trunk may, indeed, decay, 
but. this is of little moment, so long as new layers are regularly 
formed at the circumference. The tree survives, and it is diffi- 
cult to show that it is liable to death from old age in any proper 
sense of the term.” * 
However this may be, we know trees succumb to external 
causes. Nevertheless they are perennial enough to outlive aught 
else, ‘‘ To be the oldest inhabitants of the globe, to be more 
ancient than any human monument, as exhibiting in some of its 
survivors a living antiquity compared with which the moulder- 
ing relics of the earliest Egyptian civilization, the pyramids 
themselves, are but structures of yesterday.” The dragon trees, 
so called, found on the island of Tenerife, off the African coast, 
are believed to be many thousand years old. The largest is only 
15 feet in diameter and 75 feet high. Our sequoias are more 
rapid growers and attain in 3,000 to 4,000 years, which may be 
the highest age of living ones, more than double these dimensions. 
While this persistence of life is one of the attributes which in 
the battle for life must count of immeasurable advantage, the 
other characteristic of arboreal development, its elevation in 
height above everything living, is no less an advantagé over all 
competitors for light, the source of all life. Can there be any 
doubt that in this competition size must ultimately triumph and 
the undersized go to the wall? 
Endowed with these weapons of defensive and offensive war- 
fare, forest-growth, through all geologic ages during which the 
earth supported life, has endeavored and no doubt to a degree 
succeeded in gaining possession of the earth’s surface. 
As terra firma increased emerging in islands above the ocean, 
so increased the area of the forest, changing in composition to 
correspond with the change of physical and climatic conditions. 
As early as the Devonian age, when but a small part of our 
continent was formed, the mud flats and sand reefs, ever increas- 
ing by new accumulations under the action of the waves and 
currents of the ocean, were changed from a bare and lifeless 
world above tidelevel to one of forest-clad hills and dales. 
*Longevity of Trees: ‘‘Scientific papers of Asa Gray’’ (selected by 
Chas. Sargent), vol. 2, 1889, p. 71. 
