The dipterocarps are a family of hardwood, tropical trees comprising about 500 species, with about 300 species (if I’m not mistaken) located on the island of Borneo. Borneo is their center of gravity, followed by Peninsular Malaysia, South Thailand, and then Sumatra – basically the evergreen tropical rainforests of the Sunda region is where they thrive. There are many genera, like Shorea, Dipterocarpus, Anisoptera, Dryobalanops, Parashorea, Vatica, Hopea, Cotylelobium, and Neobalanocarpus, with Malay names like Meranti, Balau, Kapur, Chengal, and Keruing, among others.

Dipterocarps “can” grow very tall and large, and they form a very large proportion of the rainforest canopy here in Peninsular Malaysia. An extensive study showed that up to 57% of the emergent layer of the lowland forest in Peninsular Malaysia is composed of diperocarps. In Sarawak, dipterocarps comprise even more of the emergent and canopy layer, at 75%, while in Sabah, it can be as high as 90%. Little wonder then, that Sabah has the tallest dipterocarps ever found to date; in fact Sabah has the tallest tropical trees in the world!

Dipterocarpus species or keruing

Above – A species of Dipterocarpus or Keruing

The current tallest tropical tree in the world is a Shorea faguetiana in Tawau Hills Park, Sabah, which was taped drop measured at 88.32 meters tall. However elsewhere, this species does not grow as tall as that. In the same small park, are found many other dipterocarps that are over 80 m tall! So it is likely, that many dipterocarp species are able to attain great height or size, but due to soil conditions and local weather patterns, do not achieve such dimensions.

Another characteristic of dipterocarp forests is the group habit of the emergents. This means that the emergent trees will often be found in small groups, and not individuals, and since dipterocarps form the huge bulk of the emergent layer, it can be hypothesized that this is a habit of dipterocarps in primary forests – but that’s just my theory.

Every few years or so, there will be a mast flowering event in certain areas of the forest, where the dipterocarp trees all simultaneously flower and fruit. The “trigger” for such an event has been speculated to be a period of drought and sunspot activity. When such mast flowering occurs, the forest canopy is transformed into a brilliant mosaic of yellow, brown, orange and even purple, all in varying shades of colour.

Dipterocarp forests are already known among foresters as being the tallest and most diverse rainforests in the world. This also means – Great timber potential. Much of the lowland forests below 300 m asl that covered South East Asia have been logged or cleared for agriculture, namely palm oil. Borneo is now resembling one giant oil palm plantation, to put it mildly.

Generally, most mature dipterocarps in Peninsular Malaysia are about 30-50 meters tall, based on my experience, but in North Borneo, they regularly attain heights of 60-70+m, with some in the 80-90m range in East Sabah, which unfortunately, have been wiped out by at least 99%. Only a few remaining examples are left in the Tawau Hills Park. Other “protected” areas in eastern Sabah, like the Tabin Wildlife Reserve that in the past harbored such impressive trees, are unfortunately, almost wholly secondary forest, having been entirely logged in the past. Another area adjacent to the Tawau area, the “proposed” Sembakung area in Kalimantan, has been subjected to intense logging as well, and is now a tattered “forest” where once tall trees stood proud.

So it is almost certain there are no more areas where you will find such impressive dipterocarp trees anymore. Once a forest is logged, it will never regain its original height, as the new generation of trees will not regenerate to the previous height. In addition to that, dipterocarp trees take a VERY long time to grow to maturity. In fact, it takes on average, about 100 years for a dipterocarp to attain a canopy height of 30 m and 60 cm trunk diameter.This is based on long term observation work at FRIM (Forest Research Institute of Malaysia) and in jungle study plots.

That’s why most of the forests you see while traveling throughout Malaysia are pale shadows of their former selves, because almost all have been logged (but most people don’t realize that and often call them “virgin” forests). Taman Negara alone contains 80% of the remaining virgin lowland forests in Peninsular Malaysia while there are no more comparable areas like this (either protected or left to protect), in the WHOLE of Sarawak or Sabah.

Dipterocarpus baudii

Above – Dipterocarpus baudii, a large keruing species.

Dryobalanops aromatica

Above – Drobalanops aromatica, or kapur, a tall dipterocarp mostly confined to the East Coast of Peninsular Malaysia, like Terengganu and east Johore, where the stands have been mostly felled. It can attain a height of 70+ m tall.

Shorea leprosula

Shorea leprosula is one of the most common dipterocarps in Malaysia, a light demanding tree that can attain good size relatively quickly. Heights of 60+ meters have been recorded. It has a wide buttressed base, and the leaves have a coppery hue to them.

Shorea parvifolia

A very common tree in the (remaining) lowland and hill dipterocarp forests – Shorea parvifolia.

Dipterocarp seeds

The winged seeds/fruits of dipterocarps which lends the family their generic name. Two different species are shown here. During a mast fruiting season, their fruits are scattered all over the forest floor, but few make it to grow into trees, due to predation.

Germinating dipterocarp seed

This seed of a Dipterocarpus has already begun to germinate. The early stages of its life are the most crucial for its survival, due to predation or trampling.

Tags: , , , , ,

23 Comments to “Dipterocarp trees”

  1. Akira So says:

    I was looking for info on dipterocarps in connection with the 3 sun bears at Oakland Zoo (California, USA), whose behaviors I have been documenting. Thank you for the well-written, very informative article. Hope you will keep up the good work! Best, -Akira

  2. JungleBoy says:

    Thanks Akira.

  3. Noaf D'Cap says:

    Do you have a common name for D. baudii? I found one in the forest outside of Chiang Mai.

  4. JungleBoy says:

    @ Noaf
    I don’t think there is an English common name for D. baudii, but the Malay name for it is Keruing Bulu, which translates to Hairy Keruing. The leaves of D. baudii are hairy.

  5. mukhlisah says:

    its a very good article. keep on writing.
    thank you

  6. Dave Baskerville says:

    How would you describe/categorize the dipterocarp forests of southern Laos, (specifically in Savannkhet Province)?

  7. JungleBoy says:

    Those dipterocarp forests in southern Laos are semi evergreen, and this formation is very distinctly different from full evergreen dipterocarp forests on the Sunda Shelf. Typically with a more open, lower canopy, many deciduous trees, and less floral diversity. There are relatively few dipterocarps in this forest too.

  8. What an informative resource you are about dipterocarps! I’ve been researching woods for the book I am writing about garden furnishings for Timber Press and am alarmed at the deforestation that has taken place of these magnificent trees! I plan to include some information about this issue in my book to better inform people about sustainable and managed forests and woods. I may contact you again in the future if I have questions. Thank you!

  9. Very interesting. I’m in Sarawak right now and plan to thoroughly explore Borneo and do my part to protect the (remaining) best. Went through Thailand, but not the northern part and hope to check out Laos, Cambodia, Vietnam.

    I’m confused about dipterocarps…are they conifers or deciduous? Maybe it depends on the species? Are some broad-leafed evergreens, like magnolias in the States, or deciduous conifers, like mangroves? Please explain and send this to my email address as well as posting your response here. Thanks!

    Mousier Borneo

  10. JungleBoy says:

    @ Robert Silverman
    Dipterocarps are neither conifers nor deciduous. They are all broad leafed evergreens, at least for the species occurring in South East Asia (not sure about dipterocarps elsewhere) and are the dominant trees in the forests here (you see them everywhere). Many have a broccoli shaped crown upon maturity, and a long trunk. Sarawak probably has the greatest diversity of dipterocarps, especially if you explore Lambir National Park near Miri. Have fun!

  11. NJ says:

    Thanks for sharing your knowledge. I would like to refer to your comments on my thesis. Could you plaese give me some resources about dipterocarps and tualangs of Malaysia.

  12. JungleBoy says:

    @ NJ
    I think FRIM Kepong has a good selection of books in their library. http://www.frim.gov.my/?page_id=819
    There is a species compilation series by Soepadmo, but I forgot the name. Those are very thick books.

  13. Amanda says:

    Nice article and beautiful pictures ;)You did a Great job with the website :P Really cool ;)

  14. Amos Lim Zhen Yu says:

    Thanks for the article!
    I do have question thought, when I was in Lambir Hill National Park near Miri, Sarawak, they still call their forest the primary forest.. How really can I know which forest is virgin and which is not these days?

  15. JungleBoy says:

    Hi Amos,
    It’s not really difficult to know the difference, because virgin forest have a lot of diversity, big crowns and there is a distinct, emergent strata above the main canopy, comprising the tallest/biggest trees. Lambir Hills has all the attributes of a virgin forest. Logged forest have a poorly defined emergent layer, or none at all, and many of the canopy trees have a cone shaped appearance to their crowns, because they are not fully mature.

  16. Buren Raja says:

    What is the average durability of the kapur stump?
    What is the longest known age of a kapur stump?

    Thanks

  17. JungleBoy says:

    @ Buren

    I’m sorry, but for those questions, I think the only ones who maybe know, would be some researchers in FRIM.

  18. Wendy says:

    Hi Jungleboy,
    As a nature guide here, I find your website very useful and helpful. Thank you for taking the effort to share information for guides like us who in return will share the knowledge to others. This is a great way to inspire the public to appreciate our natural heritage. Thanks again and keep up with your fabulous work. I am slowly working on my website at this moment. Once it is up and running, I will put a link to your website, if this is ok with you. Cheers.

  19. JungleBoy says:

    @ Wendy
    Thanks for the encouraging words.

  20. Jimmy Dorrance says:

    Very well written information , thank you.

  21. Tarzan Jane says:

    Hi JungleBoy,
    Whereabouts in Sabah can we find Dipterocarpus oblongifolius (Neram) trees? Beautiful website you have here!

  22. JungleBoy says:

    Hi Tarzan Jane,

    Some of the upper rivers in the Kiulu area of Sabah (Tuaran) have Neram trees. One such river with beautiful Neram-lined riverbanks is the Mantaranau river. In the past, possibly more of the rivers in West Sabah coast had Neram trees, but intensive deforestation from shifting cultivation, plantations, logging, and general clearance have wiped out MOST of the original vegetation to the extent you just cannot tell anymore. There could be other rivers in the Sabah interior near the Sarawak/Kalimantan border that may have Dipterocarpus oblongifolius.

  23. Very enjoyable to read and informative. Thanks for sharing your tree knowledge on this particularly interesting taxa.

Leave a Reply

You can use these tags: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>