Dacrydium pectinatum at a highland heath swamp



Dacrydium pectinatum (family Podocarpaceae) is a tropical conifer with a widespread distribution, from Hainan to Sabah and Sarawak, and to Kalimantan and Sumatra. In the Philippines, it is known from the islands of Mindoro, Palawan, and the Zamboanga Peninsula on Mindanao (all in the west), and Sibuyan and eastern Luzon, where it has so far been found only from the province of Aurora's section of the Sierra Madre, the longest mountain system in the Philippines. A recent hike to Mt. Anacuao in the town in Dinalungan in Aurora yielded observations of this species.  

Developing seeds.

Cone of D. pectinatum.

  The trees were prevalent in a swampy heath at about 1100 m elevations. Grasses, members of the Cyperaceae, ferns (Blechnopsis orientalisDipteris conjugata and Sticherus truncatus), lycopodids, rushes (Equisetum sp.), and of course, ericaceous shrubs dominate this flat area. Also notable were the bright red rosettes of Drosera spatulata- these number well into the thousands. 
This species shares the habitat with other conifers as well, including Agathis philippinensis (Araucariaceae) and other podocarps such as D. beccarii, and Falcatifolium gruezoi. This heath appears to be the last stronghold of this species not only in the province but in the entirety of Luzon as well. The low altitude population along the coast, also from this province, has now been almost totally wiped out, if not already, due to mining (Ronald Achacoso, pers. comm.) Due to the toxic soils prevalent in ultramafics, this species is stunted with heights averaging 3 m tall or even less. Elsewhere in its range, the species is said to be in decline mainly due to habitat conversion for palm oil plantations and shifting agriculture. See here.


Agathis philippinensis being tapped for its resin. The local name is 'almaciga'.


Dacrydium beccarii occurs sympatrically with D. pectinatum.

At its upper altitudinal range at above 1000 m, the species appears to have an affinity with water-logged habitats with poor soils. In Sabah, the trees are found in ultramafics. The province of Aurora may be the only geographical area in the world where D. pectinatum occurs in both ultramafics and heath. 

Habitat of D. pectinatum. Note an individual along the tree line. 

As expected of habitats with poor soils, carnivorous plants abound. These include: Nepenthes alata, N. ventricosa, and Drosera spatulata. Despite the close proximity of the two Nepenthes species with one another, no plant of apparent hybrid nature was seen.





I was informed by one of guides during the climb that a wealthy Chinese logger named Mr. Ong once used this flat area as a helipad, and that he ordered people to dig for him a large pond, with the water being fed naturally by the creek coming in around the base of the peak. The pond never prospered, primarily due to the inability of the introduced fishes to adapt to the cooler climate. Fortunately, too, his logging enterprise went nowhere. Still, we heard the familiar buzz of chainsaws as we made our descent. 

Dacrydium pectinatum is apparently not present in private collections in the Philippines. The implication of this is that if something happens to the wild populations, which are always in constant threat by mining and habitat conversion, no captive stocks are available where planting materials for possible reintroductions can be sourced.

A large example of D. pectinatum showing the characteristic pale bark and candelabra branching of this very fine tree.



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