The Online Magazine for Sustainable Seas
June, 2000 Vol.3 No. 6
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The Online Magazine for Sustainable Seas June, 2000 Vol.3 No. 6 |
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Philippine mangroves:
By C.E. Yao
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'New' mangroves species Kandelia candel (Rhizophoraceae). First sighted in Baler, Quezon, this species is now called bakauan baler (Orejas, 1999). So far, no other sighting has been reported, suggesting a very limited distribution. Sonneratia ovata (Sonneratiaceae), locally known as pagatpat baye in Siquijor and pagatpat in Bohol, was first sighted in Liloan, Maria, Siquijor in 1990 (Yao, 1997a), where a small stand of the species was observed in a lagoon, about 50 meters from the highest tide. The species is closely associated with bakauan lalaki (Rhizophora apiculata), bakauan babae (R..mucronata), bakauan bato (R. stylosa), pototan lalaki (Brugiera cylindrica) and nipa (Nypa fruticans). The said stand has abundant wildings under the canopies. The species is also found in Cogtong Bay, Candijay, Bohol in pure stand and in association with pototan (B. sexangula) and has been reported in Pawa, Masbate, Masbate and Basey, Samar.
Pagatpat baye looks like pagatpat except for its shorter bole and whitish bark with shallow/narrow and grayish inner side. Leaves are light green, broadly ovate (width is the same as length) with prominent horizontal/parallel veins. The base of the short/narrow petiole is reddish. The white flowers look like those of pagatpat except for the absence of the narrow petals. The calyx is warty (rough) and the calyx lobes reddish on the inner side with the sepals attached to the edible fruit. The fruit has a depression at the base of the persistent style. The seeds are corky and granular (3mm) compared to the thin and boomerang shape of pagatpat (Yao, 1998). They are hard to germinate, but the wildlings have a very high survival rate, even after long transport. A seedling from Siquijor planted in Mualong, Loon, Bohol started fruiting after four years, when it reached a diameter at breast height of 4 cm and a height of three meters. Xylocarpus moluccensis (Meliaceae) or tabyao/cajugao in Banacon, Getafe, Bohol and Siquijor, respectively, which used to be referred to as X. mekongensis was first identified in Banacon, Getafe, Bohol by Homer Gonzales in 1996 through its pneumatophores. The species was also sighted in 1998 in several municipalities in Bohol (Candijay, Mabini, Inabanga and Tagbilaran), Siquijor (Larena), Palawan (Puerto Princesa), Leyte (Palompon), and Davao del Sur (Sta. Cruz). Although not rare, tabyao was not identified as a new species because of its close resemblance to tabigi (X. granatum).
The tree has a cylindrical bole, no buttress, narrow crown and deciduous like that of the mahogany (Sweetenia macrophylla), which belongs to the same family (Meliaceae). Leaves are smaller than tabigi, dark green, with a pointed tip, swollen petiole and spreading from the axes. The leaves turn reddish before shedding off. The fruit is smaller than that of tabigi, not exceeding 12cm in diameter. The thin exocarp remains green until maturity. This species is easily distinguished by its blunt/conical pneumatophores that reach 20cm high and 3-4 cm in diameter. The bark is brown, resembling that of mahogany. Like tabigi, tabyao occurs along riverbanks with saltwater effluence and at the back of mangroves that are inundated less than 20 times a month.
Bakauan hybrid was first reported in 1984 in Dewey island Bais City (Yao 1987,1999) but is also present in Villadolid, Carcar, Cebu, Handayan Island, Getafe and Pangan-an island, Calape of Bohol (Yao,1999), and Tiguib, Ayungon, Negros Oriental. Gonzales (personal communication) reported that the species is also found in Palawan and Jolo, Sulo. According to Vande Vusse (personal communication) the species could be the R. lamarkii, the sterile hybrid of R. apiculata and R. stylosa (Tomlinson, 1986). The species is similar to bakauan babae with its dark green and broader leaves. It has 2 flowers (rarely 4) on a short stalk located within the leaf whorl. The flower bud is whitish and angular and can easily be distinguished from that of bakauan lalaki, which is rounded with a brownish streak. The style is shorter than that of the bakauan babae and has a pinkish tip. Where the bakauan hybrid is found, both the bakauan lalaki and bakauan bato are always. The tree bears flower but does not seem to develop propagules, except in one case in Okiot, Dewey Island, Bais City, which was reported to have developed propagules in 1988. The propagules were described as "much bigger and longer" than that of bakauan babae.
The "new" mangrove associates have already been identified, but are not listed as mangrove associates. These include the following: Diospyrus ferrea (Philippine ebony/batulinao/Century Tree) is the only mangrove associate species of Family Ebinaceae. It is a small tree with simple, alternate, obovate, and leathery leaf and white or pale yellow flowers. The fruit turns red orange or purple when ripe (Department of Agriculture,1999). The bark is charcoal gray to blackish with a whitish streak. The tree is commonly found on rocky cliffs on the shore.
The tree may be inundated in some sites, such as Gubat, Sorsogon and Lianga, Surigao del Norte where it is found alongside tangal, pagatpat, bungalon, tabau and tabigi, respectively. The species is common in Panglao, Bohol. In the Samar-Leyte area, where it is called batulinao, the species is a popular bonsai item for export to Taiwan at Php150 to Php500 apiece. The Ecosystem Research and Development Services (ERDS) of DENR-Region 8 is helping coastal communities promote the mangrove bonsai by propagating the species through cuttings using root hormones. Cordia subcordata (balu, or in Siquijor alagot-ot) has a simple heart-shaped leave and long petiole. The flower is bright orange (3-4cm in diameter) with a tube-like receptacle. The fruit is round (2cm x 3cm) and has a corky exocarp with stone containing 2-3 edible seeds. The bark is smooth, whitish when young becoming brownish and rough with deep fissures as it matures. The wood is gray with a streak of red and is used locally for guitar making. Atalantea maritima (malarayap) is one of two members of Family Rutaceae considered as mangrove associates (the other is Menope angulata found in Malaysia (Tomlinson,1986). The first sighting of this species occurrede in Undol, Inabanga, Bohol in 1988, where a tree was found on a salt flat associated with nipa. The tree has also been reported in Sagnab, Loay, Bohol and Pangangan Island, Calape, Bohol at the back of mangrove areas.
The tree is solitary, less than 8cm in diameter and below 4 meters in height. The leaves are leathery, elliptic (2.5cm x 6cm) with acute apex. The short petiole tends to curve toward and touch the twigs. The leaf blade is indented/notched and marked by a whitish spot. Leaf veins at 45 degrees from midrib are parallel to each other. The bark is smooth gray with whitish spots common to citrus. Unlike in most citrus species, however, spines are conspicuously absent. References: Agriculture, 1999. Batulinao's lucky charm running out?
Agriculture Magazine, March, 1999
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