Tlie Forests of the Philippines. 575 



has not been materially changed. They form the source from 

 which the inhabitants of the Islands may draw and are drawing 

 their main supplies of timber, and also include the protective 

 forests of the high mountain regions. They cover approximately 

 one-third of the total area of the Islands. 



II. The Climate of the Philippines. 



The average annual rainfall of the Philippines shows pro- 

 nounced variations in different parts of the Archipelago, ranging 

 from 900 millimeters (36 inches) to 4,000 millimeters (160 

 inches). The heaviest rains occur during the summer and 

 autumn months (June to October), which is properly called the 

 rainy season. The entire Islands are well watered during these 

 months. During the winter months (November, December, 

 January and February) the northeast monsoon rains continue to 

 water abundantly the eastern and northern coasts, thus giving the 

 Pacific coasts and the islands bordering the large inland seas a 

 prolonged or second rainy season. The western half of central 

 and northern Luzon, the western coasts of Mindoro and Panay, 

 the Calamianes group, and small areas in other portions of the 

 Islands receive little rainfall from this monsoon, because of in- 

 tervening mountain masses. Thus a prolonged, comparatively 

 dry season with only occasional showers prevails in these regions 

 for the six months from November to May. In the other portions 

 of the Islands, this dry season varies from two to four months and 

 is more frequently interspersed with showers. In some places the 

 showers are so frequent that there is an entire absence of a dry 

 season. Thus, it will be seen that there are two distinct climates, 

 one in which the dry season is long and pronounced and another 

 in which the dry season is shorter and less pronounced and some- 

 times wanting. In the former region, the forests during this 

 season shed a portion of their leaves, and some trees are even 

 entirely defoliated for a short time; in the latter, the forests are 

 generally evergreen. Though grass areas are found in both, they 

 more quickly establish themselves in the drier belt. It is a 

 general rule that throughout the Islands during the long or short 

 dry seasons the amount of rainfall in local showers, and the 



