Tour de' Sarawak - The place where paddy cannot grow (I)

I was told that Kerangas is an Iban word for 'a place where paddy cannot grow', referring to the nutrient poor soil. While rice cannot be grown in such areas, this type of forest does support a wide variety of other plants such as pitcher plants (Nepenthes sp.) many of which have specialized adaptations that enables them to thrive in such inhospitable habitats. Once a prominent feature in the landscape of North Borneo, Kerangas forests are quickly disappearing as more and more of these areas are being converted into oil palm plantations to feed the insatiable thirst for palm oil products.

The main tree species in Kerangas varies from area to area. In this particular area in Matang, there seems to be a highrer concentration of the Bornean Rhu (Gymnostoma nobile) and the conifer Dacrydium pectinatum

A trail in the Kerangas forest, showing the typical vegetation profile


The row of trees of the right hand side of the trail are Bornean rhus

The graceful profile of this tree makes it a popular candidate for landscaping. This tree is also cultivated in our local parks and gardens


The fruit capsule - as the fruit ripens, it opens up to release the winged seeds.


A seedling of Dacrydium pectinatum


Close up of the 'needles'


Moss pads often form at the base of the trees


This uncommon color form of a common kerangas/ secondary forest plant has dark reddish pink flowers as compared to the common white flowerered clone. This is the first time I have seen this clone, and it seems to be common at the Matang site, but not at the other area I visited.

'Red form' of Ploarium alternifolium. According to my friend, the flowers and the young leaves are edible and are usually cooked in Asam


'White form' or the typical form - this is the one we have locally, and is also the form occuring in nearby Bintan islands (Riau Archipelago, Indonesia)


Bromhedia finalysoniana, a common terrestrial orchid that can also be found in secondary forests. It can tolerate a variety of light conditions, ranging from deep shade to being fully exposed.


Ant plants are also common. What looks like fungal fruiting bodies are actually the paired leaves of a Dischidia spp.

Lost, found, and lost, again !

Prain's Amorphophallus (Amorphophallus prainii) is the only Amorphophallus species to have been recorded from Singapore. Whereas it is common throughout the rest of its native range (Thailand, Malaysia and parts of Indonesia), it is locally extinct. According to a friend who used to work on our native flora, the last sighting was more than a decade ago where a solitary specimen was discovered when it flowered in a hill park. It was never seen again, and repeated efforts to comb the surrounding areas did not reveal any other specimens. While it was one of the many species that have disappeared due to the rapid urbanization of the tiny island state, losing the species so soon after its rediscovery certainly dealt a heavy blow to those of us who were passionate about saving our native flora.

I first encountered A. prainii win the coastal dipterocarp forests of Penang, where the plants were found growing amongst the giant granite boulders in deep shade. More recently, while trekking in the highland forests, I finally had the opportunity to photograph this beautiful aroid growing on a disturbed hill side at about 1,200m. Each leaf was at least 3m in height, and our orang asli friends (native aboriginal tribes) told us that they would occasionally harvest the tubers for food.

Just how steep was the terrain where the Amorphophallus was growing ? This tiny cascade next to the growing area tells it all -


The unmistakable giant leaves of A prainii


A closer look at the leaf stalk


Closer to home, we had the privilege of photographing a flowering specimen in Bear's garden. Fortunately for the photographer, it was just starting to unfurl and he was spared the nauseating stench.

Photo copyrights: HW Choy


With part of the spathe cut off:


Close up of the appendage, male and female zones:

Dangerous liaisons (I)

This tiny flower is no more than 1cm across, but one should not be fooled by its size or fragile beauty. Known as the Asiatic witchweed, Striga asiatica is one of the most obnoxious of root parasites, infecting many of the important food crops from the grass family such as rice, sugarcane, millet and sorghum. An outbreak of this hemiparasite in marginal areas of agriculture (especially those located in semi arid lands) can plunge communities reliant on subsistence farming into starvation and poverty.

The plant is self fertile and able to spread rapidly, producing 500 to 1,000 minute seeds in a single seed pod. The thousands of microscopic seeds are dispersed by wind, water or animals. While this species is native to Asia, Africa and Europe, it has since appeared in North America and the Australasia-Pacific region, where it is now an invasive weed.

The flower color is apparently highly variable, and ranges from red, orange and yellow in Africa, and shades of yellow, white and pink in Asia. This specimen (about 10cm tall), which was photographed in one of the grassy areas on the eastern side of Singapore, has cream colored flowers. Other specimens observed in the western part of the island have canary yellow flowers.

Photo copyrights: HW Choy

Recent blooms (I)

After spending almost 6 months in dry dormancy, my Amorphophallus cicatricifer finally bloomed. The putrid odor emitted by the inflorescence was reminiscent of a mix of burnt rubber and rotten eggs, which was probably due to the presence of organic suphides. The strongest odor was detected at the zone between the sterile appendage and the male flowers, and odor production lasted for about 24 hours and ceased upon shedding of pollen.


Male flowers, prior to shedding of pollen


Female flowers


Pseudodracontium harmandii, a close relative of the Amorphophallus spp., also bloomed at about the same time but had already shed its pollen.




Sterlie zone and male flowers


Close up of male flowers



Young leaf and patterning on leaf stalk

Heart of Borneo (I) - The ultimate cliff hanger

While in Sarawak last year, I had the opportunity to visit a number of interesting habitats, thanks to my hosts who were also local field experts. On the final day of my trip, my friend decided to introduce me to the limestone flora, so off we went to one of his favorite haunts which apparently also housed one of his favorite pitcher plants, Nepenthes northiana.

Standing at the bottom of the hill, I wondered how I was going to make my way up - manoeuvreing the sharp limestone rubble wouldn't be easy in the first place, and I had sustained a knee injury while hunting for Rafflesias in Kelantan earlier.

A small stream at the bottom of the hill

The limestone outcrop

But scale the limestone hill we did (somehow). Halfway up the hill, we spotted a clump of the pitcher plant hanging precariously from the cliff. If there was ever an 'ultimate cliffhanger', this had to be it.

Not a very clear image, but the large pitchers are still obvious

As we continued our ascent, we came across a mature N northiana growing on the limestone rubble. The pitchers were huge and easily more than 30cm tall - certainly amongst the largest of the lowland pitcher plants that I've seen. This one was growing semi shade and exceedingly beautiful due to the intense strips of color on the peristome.

The intense colors on the peristome

As we moved on, I got to explore the other face of the cliff with just bare rock. With the exception of North's Pitcher Plant, and a small fern, nothing else grew It was amazing to see how this specimen could thrive in such extreme conditions - the limestone rubble provided little, if any nutrients (bar those from the humus pocket in which it is rooted), and the plant is exposed to full sun and torrential rains. What a survivor !

Great things start small - the curved tip is actually an extension of the leaf, and the beginning of a new pitcher (cup) !


Those that never quite develop are still useful - these can help to provide the plant with extra support by coiling themselves onto nearby branches or plants growing in the vicinity.


A relatively new pitcher with flared peristome


The markings on this plant is less intense than the one growing in semi shade


A pitcher that's almost at the end of its life span - the lid has started to wilt

Looking back, the picture of a pitcher plant popping out of a seemingly lifeless lunar landscape almost seems surreal. But could I have expected anything less from a plant that seemed to have its origins in macabre ?


Afternote:
Nepenthes northiana was named after Marianne North, who first brought the plant to the attention of the scientific community. The original botanical illustration (below, showing the lower and upper pitchers), is housed in the Marianne North Gallery at Kew Gardens.

New species !

This was one of those very few sessions that we completely forgot about shooting the leaf and stem details of the plant. We have a very good excuse though - we've just chanced upon the flowering of an undescribed Amorphophallus species !

Photo copyrights: HW Choy
Specimen: Bear




For those who are familiar with the genus, this species apparently bears some resemblance to A. serrulatus in leaf, so it wasn't surprising that the plant was passed to my friend labelled as such. It only dawned on him that he could have stumbled onto something new as the infloresence produced didn't match those of A serrulatus. His suspicions were confirmed after sending photos of this spp to Wilbert Hetterscheid, the authority on this genus.

Top view


Close up of male flowers:


Part of the spathe cut away to show the female flowers that are near to the base:

Fabulous Hoyas (II)

Most Hoyas have fragrant flowers, but like everything else in life, there are exceptions to the rule. My H davidcummingii has been blooming regularly since the day it came back from the nursery, but I didn't detect any discernible fragrance and so I dismissed it as just another species with pretty but scentless flowers.

While I was watering my plants early one evening, I was greeted by a very disagreeable odor - somewhat like soured milk. That was enough to send me into a 'search frenzy', and soon I was inspecting every nook and cranny for half eaten yogurt packs that some teenager in the neighborhood could have conveniently discarded. With no leads but the odor still lingering in the air, I was about to call off the 'search' when I accidentally brushed against the plant - and lo and behold - this was the source of that mysterious odor ! I did not realize that the Hoya was flowering as the blooms were hidden by some of the larger foliage plants.

While I did not see any insects visiting the blooms that evening, it's probable that this Hoya may be relying on the uniqe 'scent' to attract beetles to pollinate them. It's not too far fetched if we consider how many of the other closely related members in the family (notably the Stapeliads) bears flowers that emit foul odors to attract carrion flies and beetles for pollination !

The weird 'scent' aside, H davidcummingii is a rather compact vine and flowers regularly under favorable conditions. It's thus a perfect candidate for apartment dwellers who cannot afford the space for the larger sprawlers in the genus, so don't put it off your list just yet !

Photo copyrights: HW Choy