PHILIPPINE SOILS. 



293 



JAN. FEB- MAR. APR. MAY JUNE JULY. AUG SEPT. OCT. NOV DEC. 



FIG. 5. — Mean rainfall in the eastern portion of the Philippine Archipelago. 



"This differentiation of rainfall into the eastern and western types may 

 not be complete ; for example, there is but one weather station in Mindoro 

 and while it and probably the remainder of the lower portions of the 

 island fall in Avith the western type it is believed that the rainfall in the 

 high mountains is very heavy, due to the fact that the narrow neck of 

 Luzon in Ta3'abas allows the rain clouds to pass over and precipitation 

 to take place in the high altitudes of Mindoro. However, in general and 

 in particular in those provinces contiguous to Manila, namely, Eizal, 

 Bulacan, Bataan, and parts of others such as Zambales, Cavite, Batangas, 

 and Mindoro, the dry season is very pronounced, so much so that it is 

 impossible successfully to raise such crops as coconuts, hemp and tobacco, 

 or others that are similarly dependent on a ground water table at an 

 even depth, or a practically constant available water supply in the soil 

 (chresard) which can be maintained only by a well distributed precipita- 

 tion or by irrigation. Some variation is noted in the eastern part of the 

 Islands due to the topography of the regions ; some of these are somewhat 

 differentiated into wet and dry seasons, but there is sufficient rainfall 

 during even the driest months so as not to interfere seriously with staple 

 crops dependent on continuous rainfall. It is sometimes stated that in 

 certain places in the eastern part of the Archipelago the seasons are op- 

 posite to those of Manila. It is true that at a few stations in the eastern 

 zone, for example Legaspi, G-ubat, Surigao, Tandang, and Caraga, the 

 minimum precipitation of the year is during the months from June to 



