514 



The Philippine Journal of Science 



1914 



of the dipterocarps in the various areas in Bataan (fig. 6), we 

 find that those along the trail, where there has been very con- 

 siderable cutting, grow faster than any of the others. Those 

 in type area A, where there has been less cutting, and those in 

 the virgin forest of type area B have about the same rate of 

 growth. These curves do not show the rate of growth of trees 

 less than 20 centimeters in diameter. If the smaller sizes were 

 included, the dipterocarps on type area A would show faster rates 

 of growth than those on type area B, Those on type area C, at 

 a higher elevation, have a still slower rate of growth than those 



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Fio. 9. Ratee of growth of trees of class HI. 



on type area B. The last point on the curve for type area C 

 was calculated, but it is probably not far from correct. 



In fig. 9, in which the rates of growth of tree class III in 

 the different areas are compared, it will be seen that the trail 

 trees again make the fastest growth, those on type area A are 

 next, while the growth of those on type area B is still slower. 

 The curve for tree class III on type area C shows a more rapid 

 rate of growth than that for type area B. This faster rate of 

 growth in type area C is probably connected with the more 

 open condition of the forest at the greater elevation. 



In fig. 10, in which the rates of growth of tree class II are 



