Amazing plants in Macritchie

Macritchie is an awesome place to take a refreshing walk or for runners to enjoy some trail running. This short listicle hopes to highlight some interesting plants that will be easy to spot along the trails. For some plants that don’t flower regularly, it does take a few visits and getting used to the terrain before one can spot a couple of these plants but when you do, it is highly rewarding. Most of these plants can be found only in good primary forests such as those found in parts of Macritchie.

1. The leaf litter plant – Agrostistachys borneensis

This plant is a shrub or treelet in the understorey reaching 2 to 3 m tall.

Agrostistachys borneensis

 It’s easily recognizable from the long leaves that capture leaf litter in between its leaves. How clever, making its own compost!

Agrostistachys borneensis

As seen in this photo below, the plants send adventitious roots from in between its leaves to the leaf litter.  Again, what a clever plant that recycles waste.

Agrostistachys borneensis


2. A wild relative of the mangosteen – Garcinia griffithii.

Wild relatives of agricultural crops are always important to have. Agricultural crops have limited genetic diversity and can be prone to diseases caused by fungi or bacteria. Wild relatives can be used to breed in new traits for disease resistance. Often the source of these wild relatives are found in natural habitats such as primary rainforests.  It is interesting that the fruits are ripe at the same time as the Mangosteen season that occurs mainly from July to September.


The tree is quite distinct and you can see the thinner branches sticking out almost perpendicular to the main trunk 

Garcinia griffithii

Look closely and you will see the fruits hanging from the branches.  The leaves of the genus are opposite and have distinct veins.

Garcinia griffithii

Here’s more info on the Mangosteen we eat which is Garcinia mangostana – which is referred to as the Queen of Fruits.  It is thought that mangosteens we eat originate from a natural hybridisation of two species Garcinia malaccensis and G. hombrioniana.  It is quite surprising that the mangosteen reproduces from seeds which are not fertilised (a phenomenon called apomixis).  This means that the mangosteens we eat are genetic clones of the first natural hybrids.  But there are variations that occur in the mangosteen so it is plausible that the mangosteen arose from different hybridisations and not from one.  One such cultivar is given the cultivar name ‘Mesta’ (so in full it would be Garcinia mangostana ‘Mesta’.  You will find it in some mangosteen shops being sold as Japanese mangosteens.  These have a “sharp pointed bottom”  as described in the blog i eat i shoot i post.  (Botanical term for such a shape – obovoid). This particular cultivar has very tiny seeds so it feels like it is seedless!


3.  Wild nutmeg – Knema conferta

 Sometimes walking along the trails (and not running) allows one to spot things on the forest floor that you would otherwise miss.  So stop and observe the leaf litter around and you might just spot something interesting like this wild nutmeg for example.  This has a bright red aril (flesh surrounding a seed, mainly to attract dispersers such as birds or bigger animals like monkeys.  The flesh of the durian for example is also the aril of the fruit).  Unlike the cultivated nutmeg (Myristica fragrans) the aril of Knema conferta covers the entire seed and is not divided into strips.

Horsfieldia sp_2Myristica fragrans

4.  The petai tree – Parkia speciosa

Have you eaten the petai beans?  Its a sort of delicacy usually cooked in sambal with ikan bilis.  People who enjoy it have an acquired taste for it – it can be pungent and bitter hence exciting and interesting to eat.  Known colloquially as the stink bean, the strong taste and the smell is persistent in the urine a day or two after consumption.  It may sound off-putting but take a look at a picture of this dish which uses the beans.   The tree is fairly common along the boardwalk along Macritchie near the water’s edge and the plant flowers and fruits quite frequently.  Here is a cluster of legumes (the correct term for the valved fruits of plants that belong to the peanut family Fabaceae).  

Parkia speciosa

The knob-like structure on top of the stalk is a cluster of many tiny flowers and each can be pollinated to form the long curvy legumes you see above.  They used to be called “getuk getuk” by children who would use it to knock each others’ heads.  Such were the preoccupation before smartphones totally ruined the child’s interaction with nature.

Parkia speciosa

Besides providing children with endless fun, the tree is biologically interesting.  As a legume, it would have root nodules that contain bacteria known as rhizobia that help it covert nitrogen gas from the air to a useable form to help plant growth.  Its like the plant has a way of making its own fertilizer.  It is also pollinated by bats – see this webpage that has very endearing illustrations and a nice write-up on petais and bats.  If there are no flowers or fruits to indicate the tree, a good way is to look out for the leaves which are twice-pinnate with leaflets which are tiny.  Look closer and you will see that at the base of the petioles holding the small leaflets are glands that exude nectar.  These attract ants which help defend the plant against herbivores.

Parkia speciosa


5.  Wild Ixora – Ixora congesta

This ixora goes by the common name Jarum Jarum which means bunch of needles, referring to the unopened flowers.  See more pictures of this “most conspicuous of our wild ixoras” in the WildSingapore page 

Ixora congesta

It certainly brightens the trails along Macritchie with its bright orange flowers.  It belongs to the coffee family Rubiaceae and certainly will make a nice ornamental plant or wayside bush.

Ixora congesta 


6.  The purple Thottea – Thottea grandiflora

Occasionally, this plant will flower and when it does, these curious looking flowers appear.  It is featured also in the Bird Ecology Study Group post on plants in Macritchie.  Its a close relative of the Dutchman’s pipe vines that have pretty large and similarly coloured flowers – such as Aristolochia grandiflora

Thottea grandiflora

 The plant is larval food for some beautiful butterflies.

Thottea grandiflora_3

And just a couple of years ago a new species of Thottea was discovered right here in Singapore in the Western Catchment forest.  

In local webpages, the purple thottea gets featured in articles on Macritchie, highlighting the fact that you don’t get to see this plant in any other forest type.  See these following sites for good write-ups on the flora found in Macrtichie  – Nature Watch article rainforest rojak: plants of macritchie nature trail, singapore and Tidechaser’s blogpost Macritchie Reservoir Park.

7.  Jelutong – Dyera costulata

If you see these woody pods on the forest floor, look up an you are certain to see a lofty tree with a crown that shoots above the canopy.  To further confirm its identity, the leaves are arranged in whorls of 5 to 8.


It is rather interesting to note that this tree belongs to the periwinkle family and indeed it is the largest plant in that family that includes climbers like the Allamanda, small trees like the Frangipani and bigger ones like the Pulai. The Pulai is a common wayside tree and often flowers synchronously, wafting its perfume along our estates and roads.  

The jelutong has been described by E.J.H. Corner as contributing to the fullness of the canopy and commonly rising above the canopy.  Along the water’s edge boardwalk in Macritchie, the one closer to Lornie Road, a few of these magnificent trees can be spotted.  Corner (1997), in the Wayside Trees of Malaya, describes the crown being “dense, dome-like and composed of many ascending limbs each of which ends in a conical head of foliage like a minaret.”  Its a handsome tree and not difficult to spot taking into account the fallen pods, whorled leaves and crown.  If you have a binoculars or 200-300mm lens, the pods may still be seen hanging if in season.

Dyera costulata

Dyera costulata


8.   The keruing belimbing – Dipterocarpus grandiflorus

The Malay name keruing is the name given to this genus of timber trees.  Belimbing is the qualifying epithet given to this keruing because the calyx tube beneath the wings have 5 prominent ridges making it look like a starfruit (belimbing).  The scientific name is also very descriptive with Dipterocarpus literally meaning 2-wnged fruit.  The specfiic epithet refers to the large flowers of this species.  This is an important tree for tropical rainforests.  It is a tree of primary rainforests, rarely secondary rainforests and where it is found is an indication of a mature and good quality rainforest in Singapore.

Dipterocarps are very slow growing trees and hence pack their timber densely, making them ideal for making timber.   These trees over may years have been logged for their timber and part of the reason why forests were so economically valuable.  Of course primary forests are now cleared to make way for oil palm plantations and other developments.  

The 2-winged fruit amongst the leaves of the tree.  One can recognise the leaves of the family Dipterocarpaceae generally by the veins that arise from a 45-degree angle from the midrib.

Dipterocarpus grandiflorus

 Remember to look up when you see the fruits on the forest floor.  You are likely to see the parent tree and that is a great connection to make.  

Dipterocarpus grandiflorus

The flowers are really pretty but the tree only blooms during the mass-flowering and fruiting (also known as masting) of this family of plants (along with other plant species that join in).  This occurs usually after a dry spell and for the plant family Dipterocarpaceae happens between a 2-7 year time interval, often correlating to El Nino years

Dipterocarpus grandiflorus

9. The common mahang – Macaranga bancana

This plant is quite common throughout our forests and even in disturbed areas.  But along the trails in Macritchie, one can easily find this ant-plant so looking for it will be easy.  Once you find it, you can marvel at the biology of this plant.  In the photo below starting from the top of the main stem, you will see ants feeding on white food bodies called Beccaria bodies on the lower surface of the leaf like structure called a stipule.  In other plants the stipules function to protect a young bud and fall off after the new leaf forms but here the stipule persists and curves into a dark purplish dome and continue to offer food and shelter to the ants.  In return for the food, it is presumed that the ants offer protection to this plant from herbivores.  That’s not all – the ants that live in the hollow of the stem farm scale insects.  These scale insects feed on the sap of the plant and exude a honey dew from their behinds and the ants feed on that sugary liquid- this is called cultivation mutualism and a handful of species in the living world carry this out besides humans.

 Macaranga bancana

10.   Kayu Pontianak – Parishia insignis

The final one for this list of 10 is a special tree.  It is listed as a heritage tree in Singapore and for the one in Bukit Timah Nature Reserve, it has been protected by a lightning conductor cable.  This is a relative of the mango trees and is deciduous – meaning it sheds it leaves.  In the tropics like Singapore, probably due to a dry spell.  The leaflets on its pinnate leaves have been observed to wither red so this tree might just be losing it leaves when the picture was taken.  


Parishia insignis




Enchanting Forests

After a weary week at work, i thought the guided walk would drain me further but it did otherwise.

A two hour walk seemed like 15 mins. It was raining the entire morning and at the walk it drizzled. The air was cool and it was comfortable. Visually, my eyes were treated to different hues of green and brown leaves of the leaf litter and brown of the tree trunks and fallen logs. I felt like I was in some story book description of an enchanted forest. I practiced mindfulness and walk at a slow pace, all the time breathing peacefully and guided unhurried. I felt revitalized and every creature we spotted and observed made it even better. I guess this is what people mean by bathing in the forest. The air and surrounding is just so comforting, healing and revitalizing. The only thing that marred the perfect morning was a condominium launch.

How anyone could cut down a patch of forest is beyond me. Firstly, they must have not been in the forest to appreciate it enough. Secondly, they must not know that there are thousands of living things in a patch of forest. Thirdly, they must have had a childhood void of walks in nature (I feel bad saying this but seriously, I think a childhood walk in the forest must surely leave some good memories) . Fourthly, they must not appreciate plants for the oxygen we breathe. Fifthly, they must not have seen a colugo carrying its baby gliding form tree to tree. Sixthly, they must think they have no responsibility over our natural heritage. 7thly, they must really think people want concrete instead of greenery. 8thly, they prefer shopping centres instead of walks in the peaceful forests. The list can go on. Is it a lack of understanding of the complexity and rich diversity that makes a forest so vulnerable or is it a lack of attachment to our forests?

Anyway, the quest goes on and we must be tireless in protecting what must be the only original thing left in Singapore – our primary forests. And the best way forward is education. If we want our primary forests to exist for future generations to enjoy and take a peaceful walk in a highly strung society – more people need to understand the value of the forest, either to our mental health or in its rich diversity.



Curiosities in our forests

Today’s fieldtrip with  some ex-students and their friend who are now doing their undergraduate studies in Biology reminded me how much one can discover in our forests and also the fact that my peers and I are ushering a new generation of biologists.  What better way to do this than to have a walk in the forest and chat.  It was an easy-going field trip and with no students to really look after, the company of these junior biologists was a real privilege as I brought them to a part of the forest I had often frequented as an undergrad with my peers as well.  We started off with a breakfast of prata of course.  I heard them chatter along as we made our way through the trails and they uttered terms they had learnt in the past few years (such as “tropical niche conservatism”) and also heard them speak of their professors in university and the field trips they had done themselves.  

In the forest, things appear when you are not looking for it.  I have heard of people doing  theses on animals or plants that everyone else had seen except themselves.  



Boyi and June Eng spotted a Colugo.  It looks like a mouse-deer doesn’t it? Except that it glides in the air.  The fella saw us and decided to glide away.  Luckily we had those 300 mm lenses so the shot of it looks pretty decent.  Seeing a Colugo fly “Attenboroughrised” the moment and such is the charisma of this mammal as it swooped heavily yet silently with the strange patagium stretched out against the light of the sun on a misty (ok, hazy) morning…  It is a cute animal and I am glad it lives in the canopy and shies away from humans, who seem to find it hard to share their living spaces with other animals.


Home to the peat swamp is this interesting rattan below called Daemonorops sabut.  (I am sure it is D. sabut but the leaflets I observed seem to differ from descriptions).  The spines which are arranged in whorls interlock and form galleries in which ants can be found to live in.  A strange adaptation indeed. 


The flowers below belong to Thottea grandiflora. It’s got a large (about a good-sized pear) cinderalla skirt for its flowers, fit for a forest fairy.  Extracts from the roots of this smallish shrub are used in traditional medicine to treat diabetes and most recently tested on mice.


Stamens and style underneath.


The bat lily (Tacca integrifolia) is not uncommon but is glorious when it flowers.  Very attractively gothic.  It must be attracting something important if it goes to such lengths to look so dramatic!  The pollination syndrome is something scientists find hard to answer as well. See the paper about the genus and why they look the way they do.  Answer is not straightforward!


And the beetle below looks like a dung beetle.  Yes, we do have dung beetles in Singapore.



And then there is the giant rattan, Plectocomia elongata which is one of the biggest rattan species in the world.


Finally curiosities wouldn’t be so without the curious, and I have these 3 companions (Boyi, June Eng and Charlotte) to thank for a day of discoveries.





Sungei Buloh in December – great time to go!

One of the nicest time to be in Sungei Buloh is in December.  This December is no exception but it has been extra nice as the weather has become mild yet cool.  The star attraction, of course, are the migratory birds.  Its fun looking at them, taking pictures and listening to their calls.  Sungei Buloh is well equipped with posters, guidebooks and drawings that you can almost learn what you see without a guide.  But you need to be patient.  The bird hide is such a lovely place to sit and stare at wildlife; especially at this time of the year when it is cool.


Here are some egrets and storks (Milky stork perhaps).  The white in front of the brown and green is just so lovely to look at.


Some nice waders (they look like the Common Greenshank)  See this guide from the Sungei Buloh Nature Reserve website to differentiate the waders.

I thought my kids would be interested in the waders but the Malayan monitor lizards were more exciting for them.  These lazy lounging lizards are easily encountered along the trails and even at the entrance of the reserve.



They spot another one sliding – what an adventure!  Will these monitor lizards eat them up, they wonder.  Matt forgets that he wants to go to eat ice-cream.


“I have got my eye on you…” thought the largish lizard.  The size of this makes everyone think its a crocodile.  Nice.


A feeling of excitement as the kids circumnavigate the reptilian threat.


These lizards aren’t sleepy all they time. When they manage to rouse, they can engage in fights among themselves, clawing each others’ back in the process.


This is the first time I see the Cymbidium flowering.  What a lovely wild orchid, unaltered from hybridization by man.  It looks naturally beautiful.


This is an Orb Web spider.  This one is almost 4-5 cm long from head to the end of the abdomen.



Above it are probably males or they might just be spiders hanging out on the web for scraps of food.  Its always a nice thing to tell kids that the males become snacks for the female spiders after they kiss.


The flowers hang down but the fruits face up.  Its interesting to note that the Simpoh Ayer turns its stalk after the fruit is ripe.  All the better for the pollen to fall on the bee and the fruits to be visible to birds I guess.


It starts to rain but what a good time to get a coffee at the cafe that overlooks the pond.  Buy fish food for a dollar and get the pesky kids out of your hair for the moment.  Matt sticks out his hand to feel the pitter patter of the rain drops.  I used to do that when I was a kid, these days I just rather drink a coffee and stare into the rain.




The rain stops and we get ready to leave.  By the pond is a Sonneratia alba tree. (you can tell which species it is of three species from this excellent website).  Apparently, the flowers of the Sonneratia attract the bats that pollinate the durian flowers.  So more Sonneratia more durian!  Also, this particular Sonneratia is the host trees for fireflies in Malaysia (Not sure if there are any at Sg Buloh though).  More of this wonderful tree from Ria Tan’s work.  Anyway, this tree with its persistent red stigma made me feel more Christmasy then the whole Orchard road waste of electricity light up.




Sungei Buloh 18th Anniversary Walk 2011

Today a couple of us organized by Otterman took 109 participants around Sungei Buloh as part of our yearly celebration of the opening of Sungei Buloh in 1993. I have been doing this Sungei Buloh walk ever since I was a teaching assistant at NUS.  And now as a teacher, I bring students every now and then to the wetlands reserve.  I never get bored of it and every time I promise myself to sit and be more mindful of the migratory birds every december when I am free and when they are around.  Sungei Buloh at this time of the year is extremely pleasant and cool; no mozzies along the boardwalks and bird hides so there really is no excuse not to be there.  And it costs a $1 entry fee on weekends and public holidays for adults, 50cts for kids.

Anyway, the guides today are pretty well trained for this as most of us either have been teaching assistants bringing year one NUS students around this walk or have been trained by Siva or done this many times over.  Each year Siva issues the invites for us to guide but I missed last year as I was at Resorts World Sentosa with my family on a “staycation”; well no more RWS for me until the dolphins are set free so I this year I made sure I freed up the 1st week of december to guide (I sorely regretted my stay at RWS last year and missed out on the Sungei Buloh Anniversary Walk as a result).



That’s the Otterman doing a pre-walk briefing and handing out our registration slips and handouts to participants


Every guide is is on the ball as Siva barks orders in the Sungei Buloh visitor centre.



This handout apparently was done by Ria in 2003.  The back of it has a map drawn in a similar exuberant style.

The walk is centered around the visitor centre, bird hide (Station 1) and the mangrove boardwalk.  We all hope to see the Crocodile and Otters but really the highlight of Sungei Buloh at this time of the year are the migratory birds.  It’s always amazing to contemplate that these birds are overwintering and have flown from the northern hemisphere (as far as Siberia) to feed on the Sungei Buloh wetlands or use it as an important stopover before the fly further down under to Australia AND New Zealand


Before the September-March migratory season, a few resident birds are seen on the mudflats but by December, Sg Buloh mudflats teem with waders with names like Whimbrels, Redshanks, Sandpipers etc.  They aren’t that difficult to identify if you have a guidebook, binoculars and some patience.  This is the part where I encourage everyone (including myself) to spend some quiet time at the hide to observe and get to know the waders and some of the adaptations they have (different length bills) to reach different levels of mud for their food.  The scenery plus birds is sure to calm your soul.



That is Marcus (facing you), the youngest of the guides and most energetic of us; what a way to get people excited about the wildlife we have.



It was a pleasure to have ex-students in the crowd; they haven’t changed a bit – more mature but still crazy about nature.


I wonder what Oi Yee, our other energetic guide is pointing to over the sluice gates?



A contemplative guide, Cheng Puay –  he was pretty excited about seeing the croc surface.



2 of the triplets in the family I was guiding, looking for fish, anemones and mudskippers.  Most of the time I was really talking about what could be eaten or not…  It is a great way to introduce biodiversity of the mangroves as most of the things in the mangroves can provides a service to us.

I love pickled tree-climbing crabs in Thai papaya salads.  I had them in Bangkok once and they beat some of the sashimi I have tried.



That’s Marcus gesticulating nature.


That’s Bruguiera gymnorrhiza adding to the festive spirit.


Lighter moments towards the end of the walk.



The date of the Anniversary also happens to be Otterman’s birthday so we either get cake or this time a very satisfying Punjabi meal.

Avaaz – Save the saddest dolpins

Now the campaign to save the dolphins has gone global and by reputable group Avaaz at Save the saddest dolphin online petition. What a nice phenomenon and finally I feel the dolphins might have a chance of being free and perhaps we have a chance to redeem ourselves here in Singapore. I really admire the efforts by ACRES in their “Save the Saddest Dolphins” campaign.

What was RWS thinking? Anway, how can they use excuse that the dolphins can be used for “Interactive SPA” to heal the sick and disabled children. (I have no doubt dolphins make anyone feel better but it would be so wrong if the dolphins are captive). If RWS is really sincere about this, they should donate their earnings to hospitals, hospices and other organizations who are in a better position than an integrated resort whose main expertise is food, entertainment – namely gambling, to do these things.

If you want to know how many people are signing up go look at the window on the “recent signers highlighted in the screen capture below at their website for

Post-marathon reflections – running for the captive dolpins.

I ran the Sundown full marathon on saturday evening at 10pm. Prior to that Otterman called me to wish me good luck and we started to talk about the dolphins that were being held captive and at some point would be brought to Resorts World Singapore for human entertainment. I immediately thought that I should then dedicate the run to the captive dolphins at least to put it on facebook to tell my friends and help raise awareness. And so I did, and posted on facebook that each km goes in against keeping the dolphins captive.

So when I started the race, it was really a different deal from the normal races I do where I basically go with the flow. My thoughts were of the dolphins and trust me, 42 km is a lot of time and distance to think about it. I ran with a running kaki and for the first 10 km we were chatting and telling each other how stupid we were not to train yet again.

By the 21 km mark I was alone and made the u-turn along the PCN at East Coast Parkway. I was alone with my thoughts and my pace was good, dedicating each km to the dolphins made the run a purposeful one. And as I ran close to the beach, I imagined dolphins porpoising (alternately rising above the water and submerging) freely in the sea nearby. I kept my pace and was in for a sub-6 hour timing; I had everything covered – gobbled enough power gels to keep glycogen stores up and checked my heart rate and running pace. My previous marathon was done in 6hrs 55 mins, not very good by any standards.

Then it happened yet again at the 35km, the “Wall”. I had stopped at a hydration station and took in two cups of 100-plus and wiping my face with a dry towel I had kept in a ziploc. After wiping my face, I felt instantly dizzy and had that bitter taste in my mouth. Very.. bad.. feeling. I struggled to even to stand up and walk so I laid down on the road for 10 mins. There were nice runners who saw me in trouble and ask: “Bro, you ok?”

At the 39km mark, I was barely making it, constantly spitting out the bitter taste developing in my mouth and walking very wearily. All thoughts of dolphins now disappeared and I thought how terrible for me not to finish a race I had dedicated to them. Even the thoughts of the dolpins couldn’t keep me going.

What kept me going and not fainting were thoughts of my little kids running beside me, laughing and skipping as they always do and me walking alongside my wife – as we do when we walk in the park. I had to visualise that to keep myself from giving up and that mental picture and the sounds of my kids laughter kept me going. Such is the strength of family ties, what we treasure most, our closest and dearest. It keeps us going no matter what. I finished the marathon in 6 hrs 15 mins, shaving off 40 mins from my previous timing.

What goes through a dolpin’s head when it is separated from its closest? I know as a biologist, that dolphins are highly social. If our family ties give us so much, then won’t it be the same for social and intelligent creatures? Especially sentient and highly intelligent ones like dolphins?

What bothers me about the RWS issue is that in the past we were battling ignorance of what people knew about dolpins. These days in a highly educated society like ours, what is it that we are battling to free the dolpins?

From now on, I am dedicating all the mileage I clock for the release of the dolphins and in support of the campaign by ACRES called the World’s Saddest Dolphins