4 
382 Philippine Journal of Science 1920 
Whitford ** says: 
There is little question that practically the entire land area of the 
Philippines, from sea level to the highest mountains, was originally 
covered with unbroken forest growth of some kind. 
Merrill ** says: 
It is practically certain that before the advent of man in the Philip- 
pines, the entire country was covered with unbroken forest, of one kind 
or another, from sea-level to the tops of the highest mountains, except, 
perhaps, where the vegétation had been temporarily destroyed by natural 
causes, such as volcanic eruptions. Such types of vegetation as the ex- 
tensive grass-covered hills, mountain sides, and plains, and the open 
cultivated areas, now such prominent features in the landscape, did not 
originally exist, so that the whole aspect of many localities must have 
been quite different from what it is to-day and from what has been 
its condition within historic times. When we consider that about two- 
thirds of the entire land surface of the Archipelago consists of cultivated 
areas, open grass lands, thickets, and second-growth forests, and that 
all these types of vegetation are due directly or indirectly to the 
presence of man, some idea can be obtained of the profound changes that 
have been wrought in the vegetation. of the country in past centuries. 
The earliest inhabitants—presumably the Negritos **“—were 
not skilled in any kind of agriculture and were not numerous 
enough to have been an important factor in the extermination 
of the coastal and other lowland forest. With the increase in 
population by the advent of the tribes that are now the Christian 
Filipinos, the cultivation of rice was introduced or, at any rate, 
much extended in the lowlands. This necessitated the clearing 
of large areas of level or nearly level land. If the population 
of an island increased, the area of cleared land was increased, 
until in some of the islands there was no new level land to be 
brought under wet-rice culture. In such cases some of the sur- 
plus population migrated to other islands or pushed into the 
hills and raised upland rice, which matures without irrigation 
and, therefore, can be grown on steep slopes. Even rice that 
requires much irrigation can be grown on steep mountain sides 
where level areas are made by means of retaining walls, as in 
many parts of Mountain Province, Luzon.** This method of 
cultivation is not practiced in the lowlands. All of this clearing 
means the destruction of forest; and other uses for wood, such 
* Bull. P. I. Bur. Forestry 10* (1911) 12. 
* Philip. Journ. Sei. § C 7 (1912) 149. 
* See Reed, Wm. A., Negritos of Zambales, Ethnol. Surv. Publ. ae 
(1905) 1-83, 62 pls., 2 figs. 
* See Jenks, A. E., The Bontoc Igorot, Ethnol. Surv. Publ. 1 (1905) 
266 pp., 145 pls., 9 text figs.; and Worcester, D. C., The non-Christian 
tribes of northern Luzon, Philip. Journ. Sci. 1 (1906) 791-876, 47 pls. 
