436 ^^^ Philippine Journal of Science im 



Owing to the complex character of the forest and the prom- 

 inence of a large number of trees other than dipterocarps, there 

 are many more seedlings of other species than of dipterocarps. 

 Nevertheless, the number of dipterocarp seedlings is greatly in 

 excess of that found in the better-developed dipterocarp forest 

 of northern Negros. These seedlings become established during 

 the rainy season when the moist soil furnishes an excellent seed 

 bed, and owing to the greater amount of light they are able to 

 maintain themselves better than in the denser forest of northern 

 Negros. This better development of the understories and ground 

 cover is accompanied by a better distribution of the age classes 

 of the dominant species. The forest is, therefore, much less 

 overmature than that of Negros. There are, however, certain 

 patches in the forest where the situation is especially favorable 

 for the development of dipterocarps and which show the same 

 overmature even-aged development as is found throughout the 

 whole of the northern Negros forest. Table VII illustrates this 

 character. 



Were it not for the extreme difficulty of logging this area, due 

 to the roughness of the topography, the forest would present a 

 much easier management problem than one on a well-watered 

 plain. In general, the problem presented by this forest is that 

 of removing a mature and overmature crop of dipterocarp timber 

 within as short a period of time as possible and of obtaining 

 reproduction with dipterocarps as the leading species under a 

 shelter wood, which for the most part will be made up of species 

 other than dipterocarps. The companies which are interested in 

 logging this kind of forest desire to remove dipterocarp species 

 almost exclusively. If they are compelled by rational forest 

 management to leave any timber on the ground, they much 

 prefer to leave species other than dipterocarps ; and any system 

 of management which takes this problem of utilization into ac- 

 count must look as much to dipterocarp seedlings and poles 

 already on the ground for reproduction as to dipterocarp seeds 

 that may be sown in the area from the overmature trees which 

 it is possible to leave in the remaining stand. 



THE FOREST OF NORTHERN LAGUNA 



The northeastern portion of Laguna Province, Luzon, is a 

 plateau which rises on the west with an abrupt escarpment, some 

 300 meters in height, from Laguna de Bay. From the edge of 

 this escarpment the plateau continues to rise gently toward the 

 east to the divide between the Pacific Ocean and Laguna de 

 Bay, the highest points in the plateau being from 509 to 600 



