226 



The Philippine Journal of Science 



of the year, in the same locations at depths of 10, 20, and 30 

 centimeters. 



CHEMICAL COMPOSITION 



In Table I are given chemical analyses of the soils from the 

 different altitudes. 



Table I. — Chemical analyses of soils from Mount Maquiling, Laguna 

 Province, Luzon. 



[Water-free basis, numbers give percentages.] 





Source of soil. 



Grass- 

 land. 



Diptero- 

 carp 

 forest. 



Mid- 

 moun- ' 



tain 

 forest. 



Mossy 

 forest. 





10.32 

 0.150 

 0.278 

 0.86 

 0.62 

 0.294 

 0.37 

 1.36 



10.08 

 0.137 

 0.106 

 1.01 

 0.61 

 0.241 

 0.44 

 1.06 



13.56 

 0.199 

 0.104 

 0.31 

 0.49 

 0.189 

 0.53 

 1.71 

 0.0094 



29.97 

 0.644 

 0.112 

 0.52 

 0.79 

 0.170 

 0.34 

 8.06 

 0.0082 







Lime (CaO) 

















It will be seen that none of the soils are strikingly deficient in 

 any important element and none can be considered as acid. The 

 amount of nitrogen and humus is greatest in the mossy forest, 

 where the vegetation is most dwarfed. It is to be noted that 

 the smallest amount of nitrogen and humus is shown by the 

 sample from the tall dipterocarp forest. The chemical analyses 

 of the soil, as shown in Table I, do not indicate that there is any 

 connection between the chemical composition of the soil and the 

 dwarfing of the vegetation as higher elevations are reached. 



PHYSICAL COMPOSITION 



The physical analyses of the soils from the different types of 

 vegetation are given in Table II. 



There is nothing in these analyses to indicate that all of the 

 soils should not produce a luxuriant type of vegetation. If any 

 distinction can be made, it seems that the soil of the mossy 

 forest should be the best, as this is a fine sandy loam, while the 

 soil of the dipterocarp forest and grassland is a loamy clay. 



