6 THE AMES FORESTER 



reached when mature a diameter of 12 inches and a height of 40 

 feet or more; 32% were smaller than the above but over eight 

 inches in diameter and 26 feet in height. The remaining ig% 

 were smaller than the above although still with distinct tree forms. 

 Of the total 552 species but 13 were dipterocarps. Undoubtedly 

 this represents less than one-half the total number of species on 

 the Island, but probably the proportions of different sized trees 

 that occur is representative. 



Before describing the forests further the following general 

 facts are given concerning the Islands, so as to make clearer one's 

 understanding of the situation. The Philippines lie between 

 5 and 21 degrees north latitude* about directly south of the east 

 coast of China. The group consists of n large and about 2,000 

 small islands. All of the large islands, and many of the small 

 ones, are mountainous with ranges generally extending in north- 

 erly and southerly directions. These commonly reach elevations 

 of 3,000 feet or more above sea level, the highest points being- 

 over 10,000 feet. 



Aside from the continuous warm weather, the outstanding 

 climatic feature so far as its effect on vegetation is concerned 

 is rainfall. The distribution of this is governed mostly by the 

 direction of the prevailing winds, or the monsoons as they are 

 called. From November to May the prevailing winds are from 

 the northeast, during which period most of the rainfall is on the 

 eastern or Pacific side of the islands. During this time the west- 

 ern portion of the territory, which comprises the greater bulk of 

 the area and supports the largest part of the population, has a 

 dry season. During the other monsoon the moist southwest winds 

 striking the western coasts bring the wet season. The rainfall 

 varies greatly from place to place, depending upon the effect of 

 mountain ranges and other factors, ranging from 36 to 160 inches. 

 Generally the precipitation is between 60 and 90 inches, most of 

 which falls during the wet season between June and October. 



The population is confined mostly to the sea coasts and to a few 

 of the larger valleys, there being few people back in the moun- 

 tainous areas where the virgin forests occur. Those living in 

 such regions are practically all of the non-Christian tribes, the 

 coastal population belonging to different so-called Christian tribes. 

 Tn the zone between the settlements and the virgin forests are 

 frequently large areas of grassland or of second growth timber, 

 practically all of which represent areas that were once in forest 

 but which have been cleared and cultivated and then abandoned. 



The following tabulated statement gives approximately the area 

 of land by classes : 



Class of vegetation Area in square miles Per cent 



Virgin forest .................................... 40,000 33 1-3 



Second growth forest ................... ......... 20,000 16 2-3 



Grassland ....................................... 48,000 40 



Cultivated land .................................. 12,000 10 



Total ... ........................... 120,000 100 



