588 Forestry Quarterly. 



(Bruguiera gymnorrhisa) , pototan (Bruguiera eriopetald), po- 

 totan-lalaki (Bruguiera caryophylloides), langarai {Bruguiera 

 parviflora) , and tangal (Ceriops tagal). The following principal 

 species of other families are pagatpat (Sonneratia pagatpat), pe- 

 doda pedada {Sonneratia sp.), api-api {Avicennia officinalis), 

 tabao (Lumnitzera littorea), tabigi {Xylocarpus obovatus), 

 piagao (Xylocarpus granatum) , Bxcoecaria agallocha, and dun- 

 gon-late {Heritiera I itt oralis). 



On the muddy flats at the mouths of large rivers in protected 

 bays, the pioneer plant is bacauan. Back of this come the ba- 

 cauans mixed with pototan and other species of Bruguiera, and 

 then, usually covering large areas, is langarai, mixed in varying 

 proportions with bacauan, pototan, busain, tangal, and pedada. In 

 more open bays, where the soil is mixed with considerable sand or 

 coral limestone, occurs a distinct frontal zone of pagatpat, with 

 more or less api-api. Wave-cut coral terraces often contain nearly 

 pure stands of pagatat. The inner margins of the swamps usually 

 have scattered specimens of dungon-late, tangal, piagao, tabigi, 

 and tabao. In many instances, a distinct zone of the nipa palm 

 (Nipa fruticans) is present near the upper limits of this type. 

 This palm also forms thickets along the streams where the water 

 is less brackish. Where the type is less distinct, all sorts of 

 mixtures of the above species are present. 



The capacity of this type to produce firewood and timber varies 

 according to the degree in which it has been exploited. In thickly 

 populated districts, the forest has been reduced to such an extent 

 as to render it valueless for anything except firewood. Virgin 

 areas show surprisingly large stands of poles and trees, some of 

 which are sufficiently large to produce lumber. In Mindanao, 

 valuation surveys made on a very good stand show 149 trees 

 per hectare of more than 25 centimeters (10 inches) in diameter, 

 yielding 130 cubic meters of timber per hectare, or 13,000 board 

 feet per acre. Pagatpat has been measured with a height of 31 

 meters (loi feet), a diameter, breasthigh, of 137 centimeters (54 

 inches), and a merchantable length of 17.5 meters (57 feet) ; ba- 

 cauan, a height of 28 meters (92 feet), a diameter above the stilt 

 roots of 70 centimeters (28 inches), and a merchantable length 

 of 16.5 meters (54 feet) ; pototan, a height of 28.8 meters (94 

 feet), a diameter, breast-high, of 80 centimeters (32 inches), and 



