IX, A, 5 Brown and Mathews: Dvpterocarp Forests 429 



However, only in places where light has been admitted to the 

 forest floor, due to a clearing or to a fallen tree, do rattans 

 and other vines form the dense tangles so common in the 

 poorly developed forests. The rattans and woody vines occur 

 in sufficient quantity everywhere to give character to the forest, 

 but the massive tree trunks are for the most part free from 

 clinging vegetation and one's attention is attracted to them 

 directly rather than to the minor constituents of the forest 

 (Plate VI, fig. 1). 



The heavy shade likewise prevents a dense herbaceous growth 

 in the ground cover, which is scanty. The commonest plants 

 in the ground cover are seedlings of the main tree species which 

 thickly carpet the floor in many parts of the forest. It is a 

 striking and very significant fact that tree seedlings below 7 

 centimeters in diameter are the most numerous of all the plants 

 in the forest. The extraordinary abundance of these seedlings 

 is shown in Table III. 



The data shown in Table III bring out two important facts; 

 namely, that small seedlings are present in large numbers, but 

 due to the lack of light rarely develop into larger trees, and 

 that small-sized poles are numerically the next most important 

 tree class. It is to be noted, however, that these small poles 

 which make up the bulk of the lower story are largely of species 

 other than dipterocarps. From the above one might naturally 

 conclude that if the main stand were removed without seriously 

 injuring the stand of seedlings and small poles on the ground 

 a thrifty rapid-growing young forest would be the result. Such 

 would be the result with any forest in the temperate zone 

 similarly constituted in regard to size classes, but unfortunately 

 this is not the case in the Philippines. As will be shown later, 

 it is, in the first place, entirely impossible to remove the main 

 stand without practically destroying the understory. Secondly, 

 the removal of the main stand carries with it the removal 

 of almost the entire canopy, which results in the immediate 

 death of almost all seedlings and of a large portion of the small 

 poles. 



Summing up, we see that we have in this class of forest a 

 very overmature stand, almost exactly balanced between growth 

 and decay, with the canopy and bulk of the stand concentrated 

 in the largest size classes. The heavy shade cast by the main 

 stand has prevented the development of an evenly graded under- 

 story which could be counted on to reproduce the forest and fill 

 up the blanks made by the removal of the mature and overmature 

 classes. The problem presented is that of removing within the 



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