IX, A, 5 



Brown and Mathews: Dvpterocarp Forests 



437 



Table VII. — Stand of timber on 1 hectare of virgin forest, Bataan Province, 

 Luzon, showing volume in cubic centimeters of each species and of each 

 diameter class. 



Species. 



Diameter class in centimeters. 



5 to 35. 



40. 



50. 



60. 



70. 



80. 



90. 



Shorea polysperma (tangruile) _. 



3.28 

 7.23 

 0.16 

 2.65 

 2.30 

 1.12 

 0.29 

 2.65 

 2.25 

 0.93 

 24.07 



1.68 

 8.83 



3.15 

 10.62 



4.55 

 33.09 



19.00 

 23.47 



10.60 

 22.99 



53.73 

 55.01 



Dipterocarpus grandiflorus (apitong) 



Hopea acuTtiinata (dalindingan) 



0.84 

 1.54 



1.74 

 1.74 



5.86 



3.73 







Shorea guiso (guijo) - - 







Pentacme contovt<i (white lauan) 





3.10 



7.03 











1.13 



2.81 



0.84 



12.50 

























Stromhosia philippinensis (tamayuan) 



Miscellaneous species _ . 













7.57 



12.78 



8.06 



10.34 





Total 





46.93 



30.17 



24.82 



56.28 



57.36 



60.96 



108.74 



Species. 



100. 



110. 



120. 



130. 



140. 



Total. 



Shorea polyspernui (tangruile) 







38.86 

 38.86 







134.85 



240. 75 



0.16 



13.08 

 5.58 



32.42 



39.13 

 3.78 

 5.06 

 1.77 



75.32 





24.90 



15.75 

























Shorea guiso (gruijo) - , ,. 













Pentacme contorta (white lauan) 







19.43 







Anisoptera thurij'era (palosapis) 



10.94 







27.90 



































Miscellaneous species . 













Total. -. 















35.84 



15.75 



97.15 





27.90 



551.90 





Trees less than 50 centimeters in diameter 

 Dipterocarps less than 50 centimeters in diameter 

 Trees more than 50 centimeters in diameter 

 Dipterocarps more than 50 centimeters in diameter 



Cubic meters. 

 80.409 

 32.283 

 471.49 

 433.69 



meters in elevation. Directly to the east of Laguna de Bay there 

 is very little difference of elevation over large areas. Farther 

 to the north, the country rises to the foothills of the main Cor- 

 dillera of Luzon, becoming very rough and broken, while to the 

 south the region rises gently to meet the lower slopes of Mount 

 Banahao. The main drainage throughout the central and south- 

 ern portion of the region is the Pagsanjan River, which empties 

 into Laguna de Bay below Pagsanjan. Throughout this plateau 

 all the smaller streams are very irregular in their courses, and lie 

 in narrow valleys from 20 to 30 meters below the general level 



