Dipterocarpus

Dipterocarpus is a large genus of tall trees (around 70 species) found across South-East Asia. Locally, they are commonly referred to as ‘Keruing’.

Dipterocarpus confertus

These are big trees, growing to 40 or 50 metres at their full height, and they form a big part of the upper canopy of the forests here, or stick out above the other canopy trees as ‘emergents’. Interestingly, the seeds will only germinate in shade, and for the first several years the young trees don’t tolerate direct sunlight.

Dipterocarpus tempehes

They thrive on the lowland, yellow leached clay soils that are common across much of Borneo. So much so that in fact that the lowland tropical forest is often just called ‘Dipterocarpus forest’, due to the predominance of ‘Keruing’ trees. However they always form part of a mixed forest, with other tall trees (meranti, pulai, ulin, bangris etc) also abundant, and which compete for sunlight in the upper canopy.

Dipterocarpus cornutus

They flower here in October, the mature trees producing masses of large, attractive pink-and white blooms.

Flowers of Dipterocarpus confertus

The scientific (Latin) name ‘Dipterocarpus’ means ‘two-winged fruit’. The fruits develop during the early part of the wet season (November – December), with the seeds falling in January. Their ‘wings’ are 20cm or more long, and when the seeds fall from the tree, they can spiral down, helicopter-style, and may be carried by the wind to some distance from the parent tree.

Seeds of Dipterocarpus confertus

They are valuable hardwood timber trees, and the even-grained, somewhat resinous timber has many uses, although it is susceptible to termites. Resin from the live trees was and sometimes still is collected by local people to use for water-proofing and as a source of light.

Dipterocarpus confertus seeds, almost ready to drop

Due to massive loss of habitat (logging, conversion of forest for plantations of oil palms or other timber trees etc), most if not all of the Dipterocarpus species are now classed by the IUCN as being ‘Critically endangered).

Flowers of Dipterocarpus tempehes

At the Kebun Raya Balikpapan we have 58 trees from three species in the ‘official’ collection (D. confertus, D. cornutus, and D. tempehes), though three other species (D. elongatus, D. oblongifolius and D. retusus) have also been collected.

Flowers and leaf of Dipterocarpus confertus

Sanggar Ranu Mareh Mabuan – dance troupe

Photos of dancers from the ‘Sanggar Ranu Mareh Mabuan‘ – a Dayak Ma’anyan dance studio based in Buntok, Barito Selatan, Central Kalimantan. We had the pleasure of watching them perform at the wedding of Dini and Xavier in Palangkaraya.

These young performers were fabulous – tightly choreographed, exciting, professional, colourful, tireless, amazingly agile – and with some of the nicest smiles you’re likely to find anywhere…

 

Mimosa – the ‘Shy princess’

At the Kebun Raya Balikpapan (Balikpapan Botanical Garden), five different species of Mimosa have been identified.

There are over 400 species of Mimosa worldwide, most of which originate in South and Central America. But many of them are now found in tropical regions around the globe. They generally tolerate a range of conditions, thrive in disturbed areas and poor soils – and in many places have become a serious problem as invasive weeds.

Mimosa, particularly the low creeping Mimosa pudica, is locally known as Putri malu – the ‘Shy princess’. In fact this matches the Latin ‘pudica‘, which also means ‘shy’ or ‘bashful’. The plant has this name because of its sensitivity to touch. The compound leaves retract, fold up and droop instantly when touched. Presumably this has evolved as a defence against predation. After a few minutes the leaves once again become open and erect.

It likes open, sunny positions and prefers relatively poor soils. Children of course have great fun playing with the Mimosa pudica plants, making their leaves do the bashful trick.

Mimosa pigra has flowers which resemble those of Mimosa pudica, but the plant is much taller. Indeed it can grow up to several metres tall – though those at the Kebun Raya Balikpapan are less than two metres in height.

Its stems have sharp thorns between the leaf junctions. Like the other Mimosa species, the leaves are sensitive to touch, and also curl up at nighttime.

Mimosa pigra is included in the list of the ‘world’s 100 worst invasive plant species’. In Australia, one of 20 countries where it is known to grow, it is a declared ‘noxious weed’, and boasts a number ten ranking in the list of ‘Weeds of National Significance‘.

Mimosa diplotricha is known in English as the ‘Giant sensitive plant’. The globular flowers develop into a tight cluster of seed pods. The seeds inside are adept at sticking to fur or clothing and so are easily spread.

It’s another virulent invasive plant, also originally from South and Central America, and was first seen growing in Indonesia (Java) around 1900. It has now spread to tropical areas worldwide.

This Mimosa has not been positively identified, so let’s call it Mimosa sp. It is a little taller and more ‘lanky’ than M pudica, and has bright yellow blossoms. The globe-shaped flowers of Mimosa are actually clusters of up to 100 tiny separate flowers all growing together.

At the Kebun Raya Balikpapan, it may be found in or near the same situations as M pudica.

The fifth species at the Kebun Raya Balikpapan is also (as yet) unidentified – so it’s another Mimosa sp. It has only recently been discovered there, and hasn’t yet been seen to flower.

It’s characterised by its relatively stout woody growth, the slightly zig-zag shape of its stems, and the long and very spiky thorns along the stems.

Katingan canoes

Downstream from Kasongan on the Katingan River (Central Kalimantan), few villages have road access – especially at his time of year during the rainy season.

The river IS the road, and motorised canoes (‘ces‘, ‘kelotok‘, ‘perahu‘) are the vehicles of choice.

Birds of the Balikpapan Botanical Garden – Part II

This is a followup to my previous blogpost, showcasing some of the wonderful birdlife which may be encountered at the Kebun Raya Balikpapan (Balikpapan Botanical Garden).

Collared kingfisher (Todiramphus chloris)

This lovely bird was remarkably unperturbed by my presence, and darted down from its branch several times to catch insects from the forest floor. After 5 minutes – and 65 photos – it flew off….

Asian red-eyed bulbul (Pycnonotus brunneus)

The Asian red-eyed bulbul is often seen getting grubs in lowland forests on the Malay Peninsula, Sumatra, as well as here on the island of Borneo.

I like the creamy out-of-focus green blur in the photo below. Like a bird perched in the general idea of a forest.

Banded woodpeckers (Chrysophlegma miniaceum)

They make distinctive ‘klok-klok’ sounds as their beaks strike repeatedly against the tree trunks.

This attractive (and rather raffish-looking) pair of birds were searching for ants, termites and insects.

Greater racket-tailed drongo (Dicrurus paradiseus)

These birds have a massive repertoire of songs, including perfect imitations of other forest birds. They sing sweet and loud, just beside the tracks on which I walk at the Kebun Raya – as if to attract my attention. Well, they succeed.

They are locally known as ‘Sri gunting’ (Scissor birds), because of the pair of long tail feathers.

Brown barbet (Caloramphus fuliginosus)

These birds are endemic to Borneo, where they are a ‘common resident’.

Black hornbill (Anthracoceros malayanus)

This female was seen (and heard squawking raspily) at the Kebun Raya Balikpapan. Apparently they are particularly fond of eating fruit of the forest durian

Oriental dollarbird (Eurystomus orientalis)

It was quite distant, but nicely lit by a few minutes of bright sunshine. A 560mm lens helped too…

Green imperial pigeon (Ducula aenea)

They are locally known as ‘Burung Pergam’.

For a few weeks, they were regular visitors to some trees near the Information Centre at the Kebun Raya, as they feasted (alongside a band of Long-tailed macaques) on ripe fruit of Alseodaphne elmeri.

Sooty-headed bulbul (Pycnonotus aurigaster)

Asian glossy starlings (Aplonis panayensis)

These ones are juveniles. When they grow up they take on a very shiny green-black colour – but they retain those striking red eyes.

Birds of the Balikpapan Botanical Garden

The Kebun Raya Balikpapan (Balikpapan Botanical Garden) is focussed on collecting, conserving and showcasing the unique trees, orchids and other plants of Kalimantan. Across its 307 hectares, it achieves this admirably. Most of that area consists of protected lowland dipterocarpus forest, which once blanketed much of the island of Borneo. This protected forest extends into the adjacent Hutan Lindung Sungai Wain (the Wain River Protected Forest), together forming a 10,000+ hectare window into the remarkable biodiversity of East Kalimantan.

Protection of the forest of course also protects the habitat of a huge range of other life: insects, reptiles, mammals, and… birds. So here’s a selection of just some of the birdlife I have recently encountered at the Kebun Raya. (For another selection, follow this link to view Part 2 of this post).

Chestnut-breasted malkoha (Phaenicophaeus curvirostris microrhinus)


Apart from eye colour, the female (yellow iris) and male (blue) are almost indistinguishable.

Bornean Crested Fireback (Lophura ignita in Latin, or ‘Ayam hutan’ locally)

This male was strutting proudly and showing off his fine plumage.

This female Bornean Crested Fireback is less dramatic and showy than its male partner – but no less beautiful.

Buff-rumped woodpeckers (Meiglyptes grammithorax)

The male and female are almost identical, with the male distinguished by the red patch under his eye.


They were carving out quite deep holes in the trunk of a dead tree, in pursuit of termites. So engrossed were they in that task that they let me approach within about four metres.

Pied oriental hornbill (Anthracoceros albirostris)

A wildlife photographer from Bandung (Java) visited the Kebun Raya Balikpapan recently, saying that he was very keen to see a hornbill bird while he was in Kalimantan. Not wanting to get his hopes up, I told him that they are often heard but quite rarely seen.


5 minutes later… this (female) Pied oriental hornbill.

Lesser green leafbird (Chloropsis cyanopogon)

Like its close relative the Greater green leafbird (Chloropsis sonnerati), it is found in Indonesia, Malaysia, Thailand and Myanmar. The IUCN has determined that the survival of both species is threatened by habitat loss.

Javan myna (Acridotheres javanicus)

A member of the starling family, originally found only on Java and Bali, but has spread (or been introduced) to other islands and countries.

White-bellied sea eagles (Haliaeetus leucogaster)

They are found from western India to as far east as the Solomons and New Zealand (and Australia of course), but this was the first time I’ve seen them at the KRB…

Oriental darter (Anhinga melanogaster)

They are also known as ‘snakebirds’, because only the very long neck and head is visible when the bird is immersed.


Like cormorants, they stand with their wings outstretched to dry them after swimming.

Greater coucal (Centropus sinensis bubutus)

I have seen ‘burung bubut’ before, in Central Kalimantan, but this was the first one I’d seen here in East Kalimantan.

I was even more delighted when I saw that it had just captured a little snake, which was hanging, still alive and wriggling, from its beak. (I was of course sorry for the hapless little snake, but… well, it’s a jungle out there).

The Greater coucal is a large species of (non-parasitic) cuckoo, found from western India and southern China down south as far as Java. They are reportedly becoming scarce in Kalimantan because local belief is that a medicine made from the bird’s wings is useful for healing broken bones.

Greater green leafbird (Chloropsis sonnerati)

These very attractive birds are well known in Indonesia as ‘Cucak hijau’. They have a lovely rich complex song, and are good mimics too. This one is a male.

This may lead to their extinction in the wild, because they are being heavily trapped and sold in bird markets for upwards of Rp1 million (about AU$100) each. Their owners may enter them in the birdsong competitions that are popular here. Betting and prize monies are big, and a competition winner can sell for many times the original purchase price.

20 years ago the IUCN classed them as of ‘Least concern’. But now, due to rapidly declining numbers and habitat loss, they are classed as ‘Vulnerable’.

Pacific swallow (Hirundo tahitica)

It was perched atop a tall dead tree stump protruding from the middle of a pond. They are frequently seen across southern Asia and on the islands of the Pacific.

Baccaurea parviflora

There are over 100 different species in the genus Baccaurea, which are mostly found from Thailand and Indonesia across to the western Pacific. At the Kebun Raya Balikpapan (‘KRB’ – the Balikpapan Botanical Garden) there are 99 specimens from four identified species in the collection, as well as a number of others whose precise identity has yet to be determined.

This one is Baccaurea parviflora Müll.Arg., which is known in Banjar language (along with some other species of Baccaurea) as ‘rambai’. In the Indonesian (and Malaysian) language it’s called ‘setambun’. It’s locally common from Thailand through to the islands of Sumatra and Borneo.

It grows as a shrub or small tree, up to a height to 15 metres, though usually less. So it’s an understorey tree in the rainforest, way down below the height of the big canopy trees, and the even bigger emergent trees. This one at the KRB, which was planted out as an established seedling in 2008, is currently about four metres tall.

The fruit can be eaten, though it’s acidic. Apparently it’s best when cooked. The hard timber is used to make tools and boxes and the like.

There are 15 Baccaurea parviflora specimens in the collection of the KRB, all of which were collected back in June 2006 from the nearby Sungai Wain Protected Forest (Hutan Lindung Sungai Wain). The seedlings were found and brought to the KRB by the esteemed Pak Trisno.

There are a couple of slightly unusual things about this plant. It’s ‘dioecious’, meaning that there are distinct male and female plants, with both (unsurprisingly!) required for pollination and reproduction.

The flowers grow as ‘inflorescences’, directly out of the main trunk of the tree. The flowers of the female Baccaurea parviflora are located just above ground level.

The male flowers also grow on inflorescences, which can appear anywhere on the trunk of the tree.

When the dark red berry fruits form, they just lie on the ground at the base of the tree.

The large and attractively glossy leaves grow singly, and are sort-of elliptical in shape.

Kariangau

On Wednesday I travelled with workmates from the Kebun Raya Balikpapan (Balikpapan Botanical Gardens) to collect plant specimens from the nearby region of Kariangau. Despite the even-more-than-usually hot weather, it was a really enjoyable and very interesting little expedition.

It’s only about ten kilometres away from the lowland Dipterocarpus rainforest that characterises the Kebun Raya, but it’s a very different environment, known in Borneo as ‘kerangas’. The word comes from the Dayak Iban language of West Kalimantan, and it literally means “land that can’t be used to grow rice”. It’s heathland, with nutrient-poor, sandy soils, no large trees, but many unique plant species.

We were specifically looking for two species of pitcher plants (Nepenthes, locally called ‘kantong semar’). These wonderful plants overcome the lack of soil nutrients (especially nitrogen) by being carnivorous, attracting and consuming ants and other unfortunate little creatures in their sticky ‘pitchers’.

The pitchers are actually formed as extensions to the plant’s leaves. The Nepenthes flowers are located in clusters on separate stems of the plant.

We collected two varieties: Nepenthes mirabilis and Nepenthes reinwardtiana. Each specimen was carefully extracted from the sandy soil.

Then the roots and ball of soil were wrapped in plastic to keep moisture in, and to prevent damage.

The soil acidity and moisture content were measured, and a GPS reading of the location and elevation was taken.

All these details, along with a unique code for the collector and a unique identifier for the specimen, were carefully documented. The unique identifier (known as a ‘nomor akses’) is used to keep track of the specimen when it is incorporated in the nursery at the Kebun Raya, and throughout its life after it is planted out into the ‘formal’ collections of the gardens.

The plants were then placed in larger plastic bags which were sealed, again to limit water loss before returning to the Kebun Raya.

As well as Nepenthes, we collected specimens of a ground orchid (Bromheadia finlaysoniana), and a species of the shrub Tristianopsis.

Job done, all packed up and ready to return.

Back at the Kebun Raya, black polybags had already been prepared in the nursery. Each contained equal proportions of soil, rice husks and aged manure. They were thoroughly moistened prior to planting the new specimens.

The specimens were removed from their collection bags, and excess foliage was trimmed to reduce transpiration while the plants get established in their new homes.

Each was then carefully planted into a black polybag.

Details from the field notebooks were transcribed onto forms, ready for input into the collection database.

Yellow ID tags were prepared and attached to the plant specimens, which are now ‘formally’ part of the collection of the Kebun Raya Balikpapan.