baumzaehlen - Primeval Forests & Their Trees

Up to the 1950’s, most of Peninsular Malaysia was still blanketed in primeval forest; today, particularly due to the rapidly expanding oil palm and rubber plantations, nearly all that forest has been logged over except for a few strictly protected areas, one of which is Taman Negara (meaning ”National Park”) ¹. The park is mostly pristine rainforest^{2 3 4}. Many large mammals which have been extirpated from most other parts of the world long ago still roam there – for example, elephant, wild cattle (gaur), tapir, gibbon, tiger, leopard, possibly also rhinoceros^{3 5}. Malaysia’s parks have been thought to be well-protected unlike, for example, Indonesia’s parks⁶ with their rampant illegal logging¹. However in the northern part of Taman Negara, which belongs to the state of Kelantan (1043 km² of the park’s total 4343 km²), evidence of widespread illegal selective logging has been uncovered recently; this is not widely known, but the scars are clearly visible in satellite images (e.g. Google Maps) ⁷. Nevertheless, the other parts of Taman Negara still remain by far the largest undisturbed forest in Malaysia. About 300 indigenous people (”Orang Asli”) live inside the park in a few communities⁸ close to rivers³. They are allowed to hunt and forage for food in the park³. However, they have always been sparsely distributed⁹ and their influence can only be seen near the communities and in places close to rivers and the park borders.

The park consists mostly of lowlands. The highest peak of the park, and indeed of the whole of Peninsular Malaysia, is Gunung Tahan at 2187 m. Sedimentary rocks dominate, with 83% of the park area ¹⁰. Average annual temperature at lowest elevations is approx. 26°C and varies over the year only by about 2°C ¹¹. Precipitation varies much more, the highest rainfall occurring in October to December and the lowest in February, which is the only month with mean rainfall at low elevations slightly below 100 mm ¹¹. Annual rainfall averages 2260 mm at low elevations ² and nearly 4000 mm in the mountainous regions³. Tropical cyclones (=hurricanes=typhoons) are absent¹.

The field identification of trees in tropical Asia has been said to be the greatest challenge in field botany¹², though there are also some easy-to-learn genera and species. Traditionally, a part of the challenge derives from the difficulty in deciding which fallen leaves are from any given tree as every nearby tree may be of a different species, their leaves are high above the ground and leaf forms are often roughly similar. Nowadays, however, we can use superzoom cameras: take photos of canopy leaves with the greatest magnification and further zoom the photo on the display, many details of the leaves can now be seen and so it is often possible to decide which fallen leaves are from which tree. An expert can identify the vast majority of tree species, including Dipterocarpaceae ¹³, by leaf morphology alone¹. E.g. Shorea spp. and some other related genera may still pose great difficulties because several Shorea species often grow side by side and they have quite similar leaves. The second part of the challenge is the lack of publicly available multi-access key leading to families. There is a traditional key in “Pocket Check List of Timber Trees” by Wyatt-Smith & Kochummen but it does not include all the families and uses slash characters (cut bark) too much. If you are more a “tree lover” than a forester you are unlikely to be willing to cut the bark of every tree you want to identify. “A Field Guide to the Forest Trees of Brunei Darussalam, Volume 1” edited by Ashton, Kamariah & Said has a much better key but it has been made principally for northern Borneo. If you know the family, identification is possible with the excellent keys of “Tree Flora of Malaya”, Vol. 1–4, edited by Whitmore & Ng, but Dipterocarpaceae is excluded. For Dipterocarpaceae there is a multi-access key, an old DOS program “Foresters’ CD-ROM Manual of Malesian Dipterocarps” by Newman, Burgess & Whitmore. It can be run with DOSBox in today’s operating systems. Unfortunately, there are errors in the key. An alternative is “Foresters’ Manual of Dipterocarps” by Symington, Ashton & Appanah, but it again largely relies on slash characters. All these guides apart from Symington are out-of-print and difficult to get. The third part of the challenge is, of course, the high number of tree families, genera and species. The number of tree species in Taman Negara is not known but the whole of Peninsular Malaysia has about 3100 tree species ¹. One hectare of Taman Negara’s typical lowland forest has about 200 tree species ¹⁰.

The most important tree genera at Taman Negara’s low elevations include Shorea and Dipterocarpus (Dipterocarpaceae), Elateriospermum (Euphorbiaceae), Koompassia and Intsia (Fabaceae), Syzygium (Myrtaceae) and Knema (Myristicaceae) ^{10 14 15}. The tree species richness in riparian forests is only approx. 40% of that in dryland forests². Large Dipterocarpus oblongifolius arching over the rivers are conspicuous. Other important riverside trees include Dysoxylum arborescens and D. angustifolium (Meliaceae), Intsia palembanica (Fabaceae), Pometia pinnata (taun tree, Sapindaceae), and Pterocymbium tinctorium and Pterospermum acerifolium (karnikara tree, Malvaceae) ^{2 9 10 16}. Unlike the rich ground-layer and climbing palm (Arecaceae) flora, tall tree palms are not abundant and are easy to identify, Oncosperma horridum being a common one ¹⁷. Cycas (Cycadaceae) is common in the lowland forest¹⁷.

Due to the lack of reliable height measurements, emergent tree heights have often been under-estimated, e.g. “tall evergreen trees… attain heights between 30–50 m (i.e., Tualang – Koompassia excelsa)” ¹⁰. According to my measurements (with TruPulse 200X laser), 60-metre and taller K. excelsa trees (not evergreen!) are common, the tallest individual I have measured being 69.3 m; even taller trees likely exist somewhere in the large
park. K. excelsa may be the largest and tallest tree in Taman Negara. In the fertile volcanic soils of eastern Sabah, the species can even be almost 20 m taller¹⁸. This magnificent tree has great spreading buttresses, a beautiful yellowish-white smooth columnar trunk with thick spreading limbs high above the ground and mighty, wide crown. Also many Dipterocarpaceae reach 60 m and more.

Large herbivores, particularly elephant, may have a substantial effect on the forest structure by eating and trampling plants, so creating and maintaining gaps and trails, especially around natural salt licks⁹.

There are four entrances into Taman Negara: Kuala Koh in the north, Sungai Relau in the west, Kenyir Lake in the northeast and Kuala Tahan in the south. Visitor facilities have recently been increasingly concentrated at the latter entry point. At Sungai Relau there is no longer any indoor accommodation, and the accommodation at Kuala Koh is closed (as of 2018). Trails are also concentrated around Kuala Tahan, leaving vast wilderness areas inaccessible to almost all visitors. It is possible to take a motor boat taxi from Kuala Tahan to some slightly more remote places. The peak tourist season is from April to August ⁸. It is possible to explore without a guide. Extended multi-day hikes are also possible in this park, including the strenuous trail up to the summit of Gunung Tahan (only with a guide). There are many potential dangers – like elephants, snakes, wasps, hornets, bees, dengue, leptospirosis – but the risks are low, probably lower than driving on Malaysian roads! Contrary to common belief, the risk from snakes is low, that from aggressive wasps, hornets and bees being higher ¹⁹. The most dangerous hornets nest in the ground; if they attack, run! ⁴ Of the large animals, only the elephant has attacked humans in the park area ⁸. If you see one you should immediately retreat¹⁹. The risk of malaria is minimal⁸ but that of dengue fever is real¹⁹. The biggest problem for hikers from temperate latitudes will likely be the hot, humid and rainy climate, outside the well-established trails also thorny rattans (climbing and shrubby palms). Leeches abound during and after rainy weather but are almost absent in dry weather. Lush greenery fills the view, with the continuous noise of crickets and cicadas tremendous; towards sunset the loudest cicadas produce sound volumes approaching 120 dB.

References:

1       Ashton, P. (2014): On the Forests of Tropical Asia: Lest the memory fade. Kew.

2       Zani, N. F., Suratman, M. N. & Khalid, F. (2013): Floristic Composition and Diversity in Lowland Dipterocarp and Riparian Forests of Taman Negara Pahang. 2013 IEEE Symposium on Humanities, Science and Engineering Research.https://www.researchgate.net/publication/257364242_2013_Floristic_Composition_and_Diversity_in_Lowland_Dipterocarp_and_Riparian_Forests_of_Taman_Negara_Pahang

3       Bowden, D. (2001): Taman Negara: Malaysia’s Premier National Park. New Holland.

4       Rubeli, K. (1986): Tropical Rain Forest in South-East Asia. Tropical Press.

5       http://www.asianrhinos.org.au/about_us/current_projects/sumatran_rhino_indonesia_programs/asian_rhino_specialist_group/

6       MacKinnon, K. (2005): Parks, People, and Policies: Conflicting Agendas for Forests in Southeast Asia. In Bermingham, E., Dick, C. W. & Moritz, C. (eds.): Tropical Rainforests: Past, Present, and Future. University of Chicago.

7       https://www.rainforestjournal.com/taman-negara-national-park/

8       Pers. comm. (2017)

9       Whitmore, T. C. (1984): Tropical Rain Forests of the Far East. Oxford.

10   Suratman, M. N. (2012): Tree Species Diversity and Forest Stand Structure of Pahang National Park, Malaysia. In Lameed, G. A. (ed.): Biodiversity Enrichment in a Diverse World. InTech, Rijeka.

11   https://en.climate-data.org/                                     

12   LaFrankie, J. V. (2010): Trees of Tropical Asia: An Illustrated Guide to Diversity. Black Tree.

13   Symington, C. F., Ashton, P. S. & Appanah, S. (2004): Foresters’ Manual of Dipterocarps. FRIM & Malaysian Nature Society.

14   Nizam, M. S., Norziana, J. & Latiff, A. (2006): Edaphic Relationships among Tree Species in the National Park at Merapoh, Pahang, Malaysia.

15   Nizam, M. S., Rohani, S. & Wan Juliana, W. A. (2012): Floristic Variation of Tree Communities in Two Distinct Habitats within a Forest Park in Pahang, Peninsular Malaysia. Sains Malaysiana 41(1)(2012): 1–10.

16   Kochummen, K. M. (1973): Sterculiaceae. In Whitmore, T. C.: Tree Flora of Malaya, Vol. 2. Longman.

17   Whitmore, T. C. (1998): Palms of Malaya. White Lotus.

18   http://www.nativetreesociety.org/worldtrees/sea_ei/borneo_ii.htm

19   http://www.junglecraft.com.my/

Official sites:

http://wildlife.gov.my/index.php/en/public/2016-05-10-02-34-43/taman-negara-pahang-kuala-tahan

http://wildlife.gov.my/index.php/en/info/153-kelantan-national-park-kuala-koh

http://wildlife.gov.my/index.php/en/public/2016-05-10-02-34-43/brosur

http://wildlife.gov.my/index.php/en/public/2016-05-10-02-34-43/taman-negara-terengganu-tanjung-mentong