The Forests of the Philippines. 591 



pines, because of their numerous winged seeds, will make their 

 appearance first ; the other vegetation comes more slowly, but 

 will gradually prevent the starting of a new generation of the 

 light-demanding pines. This last movement of vegetation is a 

 much slower one. Not only are the pines found in regions where 

 the dry season is pronounced, but at higher altitudes in the mossy- 

 forest belt, where the humidity is greater and more evenly dis- 

 tributed throughout the year. Thus, pines occur in abandoned 

 caingins at an altitude above 1,500 meters (4920 feet), and even 

 as high as 2,500 meters (8200 feet). Here they alternate with 

 patches of grass or mossy forest. The rainfall of this region, 

 as in many other portions of the Islands, is exceedingly heavy 

 from June to October. Especially in the deforested regions, 

 landslides occur frequently on the mountain slopes, making the 

 natural reforestation of such places difficult. In the more level 

 places, where fire lines have been established, grass patches 

 become quickly covered with pine seedlings. 



Benguet pine {Finns insularis) is the only species in the high- 

 lands of central and northern Luzon. In some places, scattered 

 pines are found in the grass lands, as low as 500 meters (1640 

 feet) altitude, bordering on the upper limits of the lauan-apitong 

 type. Pines are also found in Zambales and Mindoro. In Zam- 

 bales, two species occur: Finns insularis and Finns merkusii 

 Their altitudinal range is usually from 500 to 1,500 meters (1640 

 to 4920 feet, although scattered trees of Finns merkusii are found 

 at as low an altitude as 60 meters (200 feet). In Mondoro, Finns 

 merkusii occurs in pure stands and in open groves scattered 

 throughout the grass lands, southwest of a high mountain mass. 

 It is found as low as 60 meters (200 feet) above sea level in 

 one situation, although usually it is not found below 900 meters 

 (2950 feet). 



Measured groves of Benguet pine show a volume of 74 cubic 

 meters per hectare (7,400 board feet per acre) of trees 25 centi- 

 meters (10 inches) and over in diameter. The trees reach a 

 height of 40 meters (131 feet) and a diameter of from 90 to 100 

 centimeters (36 to 40 inches). 



In general appearance forests of Benguet pine are not unlike 

 some of the poorer stands of Western yellow pine in the Pacific 

 northwest. 



