20 



The structure and habits of growth of the abaca plant are such that it 

 requires a large and continuous supply of moisture. We invariably find 

 that the provinces where abaca cultivation is the most successful are those 

 liaving a heavy and evenly distributed rainfall. In many parts of the 

 Philippine Islands there is a long and pronounced dry season, during 

 which time there is practically no rainfall. Unless water is available for 

 irrigation, abaca can not be grown in these districts. A short drought 

 will check the growth of the plant, and a long period of dry weather will 

 destroy all growing abaca. In cei-tain parts of Albay, Davao, and some 

 other localities, while there is a so-called wet and dry season, seldom does 

 a week pass without heavy showers. The actual amount of rainfall re- 

 quired by abaca will be modified by the nature of the soil, the degree 

 of atmospheric humidity, and the methods of cultivation. Occasional 

 plowing and harrowing of the soil, beside tending to fill all crevices and 

 thus retarding the evaporation of moisture, also allows the tender and 

 fleshy roots of the abaca to penetrate further into the soil, thus enabling 

 the plant to obtain a larger supply of nourishment and moisture. 



The growth of abaca is influenced very directly by the relative humidity 

 of the atmosphere. The degree of atmospheric saturation usually follows 

 the rainfall in its variations, so that in districts where there is a heavy 

 precipitation there are also many days of excessive humidity, the effect 

 of which is almost the same as actual rain. Other conditions being the 

 same, this makes all level locations in the vicinity of large rivers or other 

 bodies of water, or along the base of hills where a constant supply of 

 underground moisture percolates through the soil, best adapted to abaca / 

 cultivation. The atmospheric conditions in southern Mindanao are exZ. 

 tremely favorable for abaca cultivation. 



The abaca plant, with its broad, heayj leaves, may be seriously injured 

 by severe windstorms. The function of the leaf is to assimilate plant 

 food. Wlien it becomes stripped and torn, as is often the case, this power 

 of assimilation is diminished and the growth of the plant is correspond- 

 ingly retarded. It is always desirable to select locations as protected as 

 possible, and it may be found necessar}' to plant trees which will serve as 

 wind-breaks. 



The following table shows the average rainfall and temperature in 

 certain parts of the Islands : 



Province. 



Albay 



La Carlota (Negros).. 

 Mamburao (Mindoro) 



Iloilo. 



Davao - 



Cebu 



Number 

 of years 

 aver- 

 aged. 



6 

 10 



2 

 4 

 2 

 C 



Temper- 

 ature. 



°C. 

 26.05 

 26.5 



Days of 

 rain. 



218.5 



154.3 



147.5 



152.6 



187 



161 



RainfaU. 



mm. 



2,750 



2,407 



2,895 



1,668 



1,853 



1,367 



